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# Miami Beach, Champlain Towers South apartment building collapse, Part 09139

## Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@Thermopile
So the PH plans, page S10, with BM42 for the cooler support do indeed have it on columns D2.1, D4, E2.1, and E4. It appears as though it was possibly Spanning out from D, over E, and half into the slab between E and H, or just from the E to H lines. Unless I'm an idiot, I can't figure out why the replacement beam called for 24ft for a 14ft 6in span. Probably just most nothing in a sea of messed up prints.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Demented, I think As-built the beam spans between E and H which is supposed to be a 23 foot span

The Penthouse corridor changed several times on plans, and they did away with Penthouse Elevator that was in early PH revisions...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

E to H was 23ft. Only issue I see there is, the entire tower stack should be more East than it is on the PH roof as seen in aerial photos. If they did move it to the E to H span, that makes the janky repair work and modifications even more janky.

4K drone video. Whoooo.
https://youtu.be/VM416Xg-oBQ

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Early plans had the HVAC plant on the D–E span, but that evolved to the wider E–H span. As far as I can see, it was built as E–H, and has remained there since. That's possibly slightly better structurally, as all 4 columns go down to the foundation. D4 goes to a transfer beam on the lobby or second floor slab (I forget which), and is replaced by D5 in the basement.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

What is this, where did it fall from?

Edit: Looks like a black steel truss of sorts, but there's no others and we've a flat roof..
Maybe it's a hermetically sealed a/c coil, eh?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

What is this, where did it fall from?

What is what? I see a bed and bedside table in an 04 unit middle bedroom, and miscellaneous collapse debris. At least describe the object, the position in the photo, and what you're thinking about it. It would also help if you identified which unit in the stack you have zoomed in on.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Red Corona)

The security video shows those floors falling from below, doesn't it?
The upper levels above x10 and x11 are missing in the first frame of the video provided to the public. See earlier post. (The first frame has two blue flashes on upper levels of x10. They appear to me to be electrical.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

The city has withheld any known directly relevant documents to the collapse I believe. Items I've asked for they have not been able to provide.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

What I DO see in Optical98's picture is a lack of rebar for about 6' to the left of the bed, after those two paltry pieces.

Is that how it's done?

spsalso

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

2
In 1964, an uncle took me to watch them take down a C&O coaling tower in Michigan. They would "wong" it with a steel ball. And then guys would torch cut the rebar. And then they'd do it again. And again. And again.

That coaling tower did NOT want to come down.

I sense a different standard of construction, compared to our current subject.

Wonder why, especially since no one lived in the coaling tower.

spsalso

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

2
The coaling tower was built to own.
The condo was built to sell.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

4
The level of posts in these threads has gone to complete crap. Hardly worth following because it's degenerated into a couple of posters ranting on about their pet theories.

#### Quote:

The upper levels above x10 and x11 are missing in the first frame of the video provided to the public. See earlier post. (The first frame has two blue flashes on upper levels of x10. They appear to me to be electrical.

Back at it again. You must think the people that have taken over will accept your theory?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (warrenslo)

The city has withheld any known directly relevant documents to the collapse I believe. Items I've asked for they have not been able to provide.

That's because it's still an active criminal investigation. Patience... in time the facts will come out. But I think we have a fairly good idea of what happened and why.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (spsalso)

That coaling tower did NOT want to come down.

I sense a different standard of construction, compared to our current subject.

Coaling towers were designed to hold many tons of coal. You still see some standing today because of the costs of demolition. Condos are designed to hold basically itself, some furniture, people and air. As we saw recently, it doesn't take much to bring one down.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Nessman)

But I think we have a fairly good idea of what happened and why.

It sounds like this group may be ready to re-cap all the theories on what, how, when, and why. Rather than rehash them all, can we make a list? I will volunteer to rake them off and organize them into a Google Sheet for all to see and refine.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I would argue the new folks went to the trouble of joining and posting here because they felt something was missing as far as theories or stringing together the chain of events that led to this disaster.

It would be great to find out it was something really simple and easy to fix so this would never happen again, but after 4 weeks or so of posts, I do not feel that will be the case. Folks have done an amazing job at identifying key vulnerabilities in the structure and provided analysis to explain the weaknesses.

The public has been blacked out of key and validating information due to so called 'crime scene status', thus this is going to probably play out for years in our court systems.

Even Building Integrity's last video post was lacking to me in content. Perhaps we are at the end of the road without sufficient validated data to crank into our models. Also it has been said that there is so much of this building that was not OEM, that it will in all likely hood, be very hard to build those models. Especially after they demolished the key remaining in tack evidence. Look at what appears to be large variations of quality of construction, latent defects or defective maintenance repair work. The materials testing will help get a feel for the general quality perhaps.

Here is a link to Building Integrity's explanation of shear walls. I had hoped he was going to get into the fact that the columns sure looked beefier in the part of the building that was still standing versus the area that had the PH. Why does there appear to be key structural robustness differences in the two parts of the buildings? That is of interest to me, and the effects of such. E.g. The elevated parking fell without taking down the building above it.... It is almost like they built up to the shear wall, then added on beyond the shear wall, but that makes no practical sense. Or designer started designing the remaining part first, but then got pressure from developer to lower costs, so margins were taken out of rest of building, but left in original to save re-design costs? Far fetched but the why the difference is very interesting..

Edit: My memory of the 1979 timeframe was long hand paper calculations with the aid of a hand held calculator, with somewhat programmable calculators being introduced in the 1970's (see second link I found with a quick Duck Duck Go).

https://www.theregister.com/2014/01/03/ten_classic...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Thermopile, I agree on his last video, and the analogy of tearing paper if at all should have been torn in a downward motion. The various column sizes are a mystery.

MaudSTL,

This platform makes it difficult to look at gathered evidence (or lacking) of a theory/hypothesis in one place..
Perhaps a spreadsheet would be helpful. How would it be made available for us to examine? Also it can't be up to one person to determine whether evidence gets added or not... Proven Evidence for a theory in one column,
Possible evidence not yet proven in another and then a column for arguments against it?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (Optical98 (Computer)25 Jul 21 02:49)

What is this, where did it fall from?
It fell from inside the unit. Entertainment center with 4 screens?

SF Charlie
Eng-Tips.com Forum Policies

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (warrenslo (Structural)25 Jul 21 04:05)

The city has withheld any known directly relevant documents to the collapse I believe. Items I've asked for they have not been able to provide.
Yes, and I notice they have successfully prevented most drone video except for the fire department's from being published.
They also hindered the residents of adjacent buildings coming and going.
Also, except for Because Surfside no one seems to have published video from adjacent balconies.
And, all their live videos have been deleted.
"respect for the victims' families"?

SF Charlie
Eng-Tips.com Forum Policies

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Thermopile)

I would argue the new folks went to the trouble of joining and posting here because they felt something was missing as far as theories or stringing together the chain of events that led to this disaster.

It would be great to find out it was something really simple and easy to fix so this would never happen again, but after 4 weeks or so of posts, I do not feel that will be the case. Folks have done an amazing job at identifying key vulnerabilities in the structure and provided analysis to explain the weaknesses.

The public has been blacked out of key and validating information due to so called 'crime scene status', thus this is going to probably play out for years in our court systems.

Even Building Integrity's last video post was lacking to me in content. Perhaps we are at the end of the road without sufficient validated data to crank into our models. Also it has been said that there is so much of this building that was not OEM, that it will in all likely hood, be very hard to build those models. Especially after they demolished the key remaining in tack evidence. Look at what appears to be large variations of quality of construction, latent defects or defective maintenance repair work. The materials testing will help get a feel for the general quality perhaps.

Here is a link to Building Integrity's explanation of shear walls. I had hoped he was going to get into the fact that the columns sure looked beefier in the part of the building that was still standing versus the area that had the PH. Why does there appear to be key structural robustness differences in the two parts of the buildings? That is of interest to me, and the effects of such. E.g. The elevated parking fell without taking down the building above it.... It is almost like they built up to the shear wall, then added on beyond the shear wall, but that makes no practical sense. Or designer started designing the remaining part first, but then got pressure from developer to lower costs, so margins were taken out of rest of building, but left in original to save re-design costs? Far fetched but the why the difference is very interesting..

I'm nearing on impossible. Much of the building turned to powder when it fell (as it seems most of what was put back was epoxy and mortar, not cement), so even material testing wont show us a clear picture of what was actually where.

Could the design differences be to have kept the BOM the same, but still build the penthouse additions? Length of rebar, volume of cement, and pallets of CMU. That could easily satisfy a client with very minimal effort in design change. Were the pile changes around the same time as the column and dimension revisions? I never saw the original geotechnical report that made them switch so close to initial construction.

@SFCharlie
The police were attempting to shut him down for weeks. Within hours of MDPD taking over control of the site, all of his streams and nest cams went down. Not sure why but they really were not happy with him.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

SF Charlie,
The Because Surfside videos were frustrating, because you couldn't see the most pertinent areas, but you could see clearly several times, people recording from 87th Terrace. And yeah the chat was juvenile.

As I posted several threads ago, any pictures or video of the front of the building (after June 24th) are impossible to find.
And when I say front, I mean the lower drive thru area that we know had damage.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Demented,

Do you know what was the MDPD's stance on the demolition of the west end? The way they have taken over the scene, labeled it a crime scene and wouldn't let AK on the scene to test anything....
Makes me think they weren't happy about it?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

In my City, Mayor’s Control Police Chief’s. Our DA actually open a can on corruption by City concerning coverup. Did not fully expose everything due to missing information, but did charge criminal actor, and it resulted in conviction by jury.
And Mayor’s are controlled by their funding sources.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Thermopile,

When Cavo signed off on the ordered to demo, she stated that it would still take 2-4 weeks before all was planned and executed. But like whiplash, it was being prepped for demo a few days later.

And well, even if MDPD answers to Cavo....doesn't mean they agreed with this decision... they're calling it a crime scene for a reason.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Optical98, What is confusing to me is why each City with a Mayor, does not have there own PD. That is typically what I see in Inc towns. Out in the Counties the Sheriff’s typically are primary. How does all this work in Miami-Dade?

Does Surfside have their own Police Force? I can see making this a criminal investigation could be because of a deliberate or stupid act was trigger, but I can also see it is to protect Miami’s Condo Money Printing operation, and perhaps somewhat to keep folks calm and not thinking ever old Condo is at risk. If folks are scared away from Condo’s on Reclaimed Ocean, what happens to South Florida’s lively hood?

And then this could be an opportunity to condemn old Condo’s on prime real estate, so Developer’s can start urban renewal again to create new fatter profits?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

The photo of a PVC pipe with trap shown by Demented in section 08 and discussed further by Thermopile and Optical98 was really interesting because it shows that when they want to zoom in on an object in a video taken from a drone flying overhead, then they can see a 2 inch diameter object clearly enough to distinguish whether it’s a pipe or an electrical cable. Yet, they can’t see another zoomed object that is 36x36 inches square in another video.

This photo also intrigued me because of its high resolution. Not seeing Demented’s reference to the video until later, I tried to find a similar photo with the same high resolution and came up with one taken from a different perspective. And when I zoomed in on the green tarp behind the air conditioning units seen in Demented’s photo, look what I found:

It shows a green tarp covering rolls of tarpaper (aka roofing felt) on a wooden base. The rolls are almost all standing on end and there are 7 rolls in each direction, giving 49 rolls on the wooden base. On top of the rolls there is also a metal object of some sort. Since rolls of tarpaper are always 3 feet wide and one of the rolls is lying on its side, it is easy to verify that the wooden base is 6x6 feet. Depending on the thickness of the tarpaper, one roll can weigh between 35 and 85 pounds. Assuming 50 pounds per roll to be on the low side, this gives about 49x50 lbs = 2450 pounds plus the weight of the wooden base and the metal object, or about 2500 pounds, or over one ton. This corresponds to about 2500/36 ft2 = about 70 lbs/ft2. This is a heavy load on the roof of the 12th floor of the building that was still standing. If the same load was later placed on the penthouse roof with its thinner slab, then it seems like it might overload the penthouse roof and cause it to collapse. I’ll leave it for someone else to determine the maximum load for the penthouse roof and what the margin might be for collapse.

It just occurred to me that the Surfside building inspector was on the roof just the day before the collapse. Do you think he saw this high concentration of tarpaper in one area? Also, we have not seen any rolls of tarpaper on the debris pile anywhere. So, perhaps there was no similar green bag with tarpaper on the penthouse roof.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I like the point Building Integrity made about the fracture in the core samples showing that the layers of the patio slab had delaminated. Basically it meant that the punch through shear forces were being resisted by much less steel than if the delam had not occurred.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

This platform makes it difficult to look at gathered evidence (or lacking) of a theory/hypothesis in one place..
Perhaps a spreadsheet would be helpful. How would it be made available for us to examine? Also it can't be up to one person to determine whether evidence gets added or not... Proven Evidence for a theory in one column,
Possible evidence not yet proven in another and then a column for arguments against it?

I am offering to be a scribe, using Google Sheets which can be publicly viewed by anyone with the link.

Here’s a starter…let’s plug in a theory and see how it works. Right now I have it set up for View permissions. We may be able to figure out a way to have multiple Editors, but for now I am going to populate it from what people tell me to put in.

The first step, after loading in a hypothesis, is to see if we need to add columns. I added No., Type, and Sub-type so we can classify and sort as the list grows.

No.
Type
Sub-type
Theory/Hypothesis <short description>
Proven Evidence
Possible Evidence Not Yet Proven
Argument Against

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

LOL Markbob, I have freely admitted to "not seeing clearly" many items on photos. I don't mind posting pics for discussion, or outright saying "what is this"?

I don't have a clue how much tar paper weighs, even looking at it on a pallet. I would venture to say if said pallet is as heavy as you say and it perhaps was sitting near a "left on" tar kettle on the eastern roof... that could be a problem. But we need to find these items on the ground at this point.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

MaudSTL

It might be easier to give each theory it's own tab? Under evidence there will likely have to be links to photos and articles etc. So it will grow, unless you don't mind inserting rows constantly.

A few theories to use for model -

Car vs Column
Roof failure from different objects, ac, tar kettle... actually their may be several
Pool Deck Failure

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

15lb tar paper is very easy to tear, so I wonder on a commercial roof would you use say 30 lb instead?

Duck Duck Go Quick Quote Find:

"Weights and Measures of Underlayment for Roofing
May 19th, 2014
Share Now:

One of the most common questions when it comes to underlayment is whether one layer of #30 felt is the same as two layers of #15 felt? The short answer is no, but understanding the reason for needing two layers and the actual differences between the grades of underlayment is probably more important to know.

The traditional underlayment that has been utilized for many years and is still used today in steep-sloped roof applications is “asphalt saturated felt.” This product is commonly referred to as “felt paper,” “#15 felt,” or “#30 felt,” “building paper,” “felt underlayment,” or simply “underlayment.”

Underlayment is utilized under a variety of materials such as; asphalt shingles, wood shingles/shakes, metal roofing, metal shingles, slate, tile, and other synthetic steep-sloped roofing coverings. Underlayment can provide many functions for the roof assembly, including temporary protection for the substrate, creating a “cushion” or leveling layer below the roof covering, or act as a separation layer between the roof covering and the substrate.

Manufacturing organic asphalt-saturated felt underlayment is a pretty straightforward process. Recycled paper is processed into a roll. Hot asphalt is then added to the roll and asphalt saturated underlayment is the result.

In the past, the felt number designation was correlated to the weight of the felt (i.e., a 15# felt weighed 15 pounds/100 square feet). However, that direct correlation to weight no longer exists. By shifting the pound symbol, 15# felt became #15 felt, which may actually weigh 7.5 to 12.5 pounds per square; #30 felt can weigh between 16 and 27 pounds per square. Simple math shows that a single layer of #30 felt today could weigh more or less than two layers of #15 depending on which end of the min/max spectrum the two types of underlayment fall.

The need for two layers of felt is driven more by the deck slope and water management than actual weight.

Felt underlayment is water-resistant, but not waterproof. Felt’s perm rating varies but not by much. Dry, #15 felt is rated at 6 perms, #30 felt at 5 perms. The thicker #30 felt is more resistant to damage during installation of the roof-covering material, and will protect the roof longer if it should somehow become exposed to weather, but only applying one layer of underlayment on a low sloped roof does not offer the proper protection against water infiltration.

The lower the slope of the roof, 2:12 up to 4:12, the greater the chance of water working its way through to the substrate. Applying two layers of underlayment in a shingle fashion where the top layer overlaps the bottom layer by about 19 inches creates a stronger barrier against any wind driven water. One layer, regardless of how thick it is, will not provide the same protection.

Underlayment is a critical component of a home’s roofing system. Several factors such as roof covering and slope affect what and how it is installed. It’s not about weight, it’s about protection. One layer of #30 felt does not offer the same protection as two layers of #15. In fact, since the designations of #15 and #30 referring to the actual weights of the underlayment no longer apply. The terms Type I and Type II now are used within the industry, respectively, making it much easier to understand when it’s appropriate to use which type of underlayment."

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Thermopile)

Optical98, What is confusing to me is why each City with a Mayor, does not have there own PD. That is typically what I see in Inc towns. Out in the Counties the Sheriff’s typically are primary. How does all this work in Miami-Dade?

Does Surfside have their own Police Force? I can see making this a criminal investigation could be because of a deliberate or stupid act was trigger, but I can also see it is to protect Miami’s Condo Money Printing operation, and perhaps somewhat to keep folks calm and not thinking ever old Condo is at risk. If folks are scared away from Condo’s on Reclaimed Ocean, what happens to South Florida’s lively hood?

And then this could be an opportunity to condemn old Condo’s on prime real estate, so Developer’s can start urban renewal again to create new fatter profits?
Surfside has a PD, but it's no bigger than 8 officers. Most things in the tri-county area are run under Good ol' boys rule with the Sherriff's association, which MDPD is a part of.

Cavo recently signed off on large construction projects with the same firm behind the FIU bridge, among some other things. It's not unreasonable at this point for MDPD to suspect a multitude of wrongdoing, especially with the Morabito name tied to the roofing contractor that seems to have been doing the work unpermitted initially. Not to mention all of the other questionable permitting situations and stuff the town officials let slide.
Other buildings all throughout the area are still getting inspected and evacuated. It's a major issue it seems that's not local to this one particular building so there definitely is going to be a massive, drawn out investigation. Unfortunately as is all too common in FL, officials being investigated are often in charge of those investigating them, and retaliation firings are all too common.

The town of surfside has also recently been looking to invest major millions into underground tunnel projects.

It was a locked down crime scene from day 1 basically.

Precision guess work based on information provided by those of questionable knowledge

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

2
MaudSTL.
A suggestion;
Add a column for the identity of contributors.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

When Cavo signed off on the ordered to demo, she stated that it would still take 2-4 weeks before all was planned and executed. But like whiplash, it was being prepped for demo a few days later.

She was working off what her advisers told her, which was reasonable advice and a reasonable fast timescale for most demolition contractors. Mark Loizeaux is not most demolition contractors, he's one of the top explosive demolition experts in the world, blowing up concrete and steel more or less continuously since he was a teenager, and now in his 70s. He is someone who can spend a few hours with the plans, walk the site, mark the spots for charges, and still pull it off with precision and just a day or two total planning. He had people back at his office helping, naturally, but he really is an artist / genius with explosives. From the sound of it, he could have done it quicker if they had signed off on his plan immediately.

That level of expertise can greatly shorten the timescale compared to reasonable estimates from advisers.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (MarkBoB2)

The photo of a PVC pipe with trap shown by Demented in section 08 and discussed further by Thermopile and Optical98 was really interesting because it shows that when they want to zoom in on an object in a video taken from a drone flying overhead, then they can see a 2 inch diameter object clearly enough to distinguish whether it’s a pipe or an electrical cable. Yet, they can’t see another zoomed object that is 36x36 inches square in another video.

This photo also intrigued me because of its high resolution. Not seeing Demented’s reference to the video until later, I tried to find a similar photo with the same high resolution and came up with one taken from a different perspective. And when I zoomed in on the green tarp behind the air conditioning units seen in Demented’s photo, look what I found:

It shows a green tarp covering rolls of tarpaper (aka roofing felt) on a wooden base. The rolls are almost all standing on end and there are 7 rolls in each direction, giving 49 rolls on the wooden base. On top of the rolls there is also a metal object of some sort. Since rolls of tarpaper are always 3 feet wide and one of the rolls is lying on its side, it is easy to verify that the wooden base is 6x6 feet. Depending on the thickness of the tarpaper, one roll can weigh between 35 and 85 pounds. Assuming 50 pounds per roll to be on the low side, this gives about 49x50 lbs = 2450 pounds plus the weight of the wooden base and the metal object, or about 2500 pounds, or over one ton. This corresponds to about 2500/36 ft2 = about 70 lbs/ft2. This is a heavy load on the roof of the 12th floor of the building that was still standing. If the same load was later placed on the penthouse roof with its thinner slab, then it seems like it might overload the penthouse roof and cause it to collapse. I’ll leave it for someone else to determine the maximum load for the penthouse roof and what the margin might be for collapse.

It just occurred to me that the Surfside building inspector was on the roof just the day before the collapse. Do you think he saw this high concentration of tarpaper in one area? Also, we have not seen any rolls of tarpaper on the debris pile anywhere. So, perhaps there was no similar green bag with tarpaper on the penthouse roof.
I am not above admitting I am wrong on something.
After all of this digging that led me up to a particular spot on the rough through permitted and unpermitted work, and having seen the TikTok video again not looking for anything other than to see if I could notice if the 20ft section leading to the garage collapsed.
Nothing stops a Trane.

Precision guess work based on information provided by those of questionable knowledge

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (waross (Electrical)25 Jul 21 17:33 MaudSTL. A suggestion; Add a column for the identity of contributors. )

I second waross motion!!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

If we have a 3/4" hole for a 5/8" anchor, what is the thickness of the roofing material? Our tar paper thickness is in there.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

MarkBoB2 and Demented........ Amen.....

Edit for Demented: Yes I can see the previous re-roofer, said I have an ingenious idea....... I can save the Association Money, by roofing over the old roof and cut requiring labor and disposable costs... and of course you now have a double roof!!!
I also see that threaded anchor ran out of depth of concrete it appears?

And looks like it collided with STEEL.... Wonder how that could happen??? Let's see 6" slab would mean 1/2" to 5/8" bottom rebar would be 5/8" plus 3/4" above bottom of slab. So top of rebar would be at 4-3/4" down to say 4-5/8" down if I did the math right in my head?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

There goes Demented showing off his pixels.....

Can u expand out a lil, where are we, on the roof, pool deck?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (waross)

MaudSTL.
A suggestion;
Add a column for the identity of contributors.
Please put me down for gravity. Thx!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

None of those pixels look like tar paper... They look like multiple layers of elastomeric roofing material?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

And we all know 'Gravity' can be a bitch!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Watching the BI video, if the slabs failed shearing down the shear wall in such a way, where are the marks of concrete against concrete? We've see scraping along the columns where slabs failed, as well as along other walls such as in the deck. I just don't see indications of shearing along the wall, as is evident as well by portions of slab clinging to and hanging from the wall. We know this are of the building also twisted in the opposite direction we would expect to see from a shearing like that. Those slabs hung on for dear life until the rebar reached it's tensile limit and snapped.

It looks to me as though it tore away, not sheared, initially at least.

At this point, I am more inclined to say the collapse originated around the E-H column span leading to upper floors collapsing, sending massive shock loads to the base of columns before the deck and possibly portions of the lower slab elsewhere in the parking garage, failed, hinging where the slab is offset, causing the pool side of the building to collapse which brings what I believe to be the 4th section collapsing down, and finally the east most wing as it was top heavy and unstable. If it were not for the elivator shaft, I think it's likely we would have seen the entire structure come down.

@Optical98. Download the original. I don't know why but uploading images turns even high res to potatos here. It's a whole lot more clear.
Top of the rubble pile, day 1, first responder photo.
3024 x 4032, iPhone 11.
So we at least have some decent quality.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I think we need to realize with MarkBoB2's calculation, that plastic Green and yellow handled bag is just the right 2500 lb static test load for a 5000 PSI rated OSHA roof anchor???

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Hanging off of a hot tar roof that was many layers thick with anchors driven down into the roof covering, and not the slab. Almost feels like we've been there before.

Precision guess work based on information provided by those of questionable knowledge

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Demented, I think that bottom black layered bit is part of a broken window frame.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@MarkBoB2, 60lbs per roll.

Precision guess work based on information provided by those of questionable knowledge

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@Demented, You are correct in thinking that pure tearing as displayed in the paper analogy would leave scrape marks along the shear wall, however that is a very black or white perspective.

In a previous post, I noted a void in the debris pile as if the remains of section 1 disappeared. We now know for a fact that there is no sinkhole that swallowed them up. Rather the pull of the collapse was significantly to the NNE.

I'm not an expert, but someone else posted a collapse video that showed just how much a weak side of a failure can be pulled aside so the question is which side of the collapsing section has more pull. We already know the answer in this case, but this raises the question of why was the big strong shear wall unable to exert the greater pull. The BI analogy nicely answers this question.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

20 rolls per pallet is typical for the heavier stuff.

As in the picture of the pallet on the roof above, they are 4 wide x 5 deep. I’m not sure how anyone sees 7x7.

20 per x 60# = 1,200 lb / pallet

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@Optical98, I don't think it is. Next to it you can see a portion of window/door sliding frame and it is different. Layers of tar appear to be on it which I can't imagine was used along side it. This layering is also evident near the elivator shaft.

@Sym P.Le
Black and white perspective indeed. It's just odd to me that we see it elsewhere in the collapse, but not there. Roof Area 2 was the only reroofing this year. Was this area recently installed with anchors? I ask because in previous threads it was speculated that weight may have been hung off an anchor above this area to load test the anchors. This was a thick roofing section per the plans. I know they weren't supposed to put anchors here, or yet at least, but their judgement in placement could have been better in places. Also, why are there instructions for full depth slab repair included in the roof anchor permit? What roofer is going to be shoring, doing full depth replacement, and epoxy injection? There are some large, rubberized hoses that can be seen near the roof anchor in the photo I posted.
Now, I have engine parts and tools all through my apartment, so I am in no position to discount someone else having what appears to be air or hydraulic lines in their unit. However, why was an air compressor recovered with roofing equipment? Seems they had gas powered sweepers and blowers, electric hammer drills and impacts. What is the air for, other than for epoxy injection?
That building inspector on the roof the day before would definitely know.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Demented, my guess is a nail gun.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

But what were they planning on nailing in the "ROOF & FACADE MAINTENANCE ANCHOR SYSTEM"

You wouldn't nail more tar paper down into the existing roof and hot tar over it...would you?

Edit: Sandblasting? Still curious how instructions this detailed for concrete repair got into the roof anchor install. Nail 2 birds with one stone?

Lets all read this aloud shall we?

dik pointed this out in thread 1.

Edited:

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Spartan5, the standard pallet in the roofing industry is 48x36 in. Looking at my photo above, each side is 2x36 inches. So one may conclude that the wooden base is not a standard pallet. You can easily count the rolls of tarpaper in each direction in the photo I provided. I counted 7 in each direction.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Demented, there was roofing equipment/supplies all over that roof, I think they were covering more than just section 2?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

96"x48" is a pretty common pallet size used by distributors of this area. Concrete will still be on 48"x36" pallets to keep the weight down for standard forklifts. A 96x48 pallet would give you 32 rolls +/- 1. ~2000lbs.

@Optical98
Covering yes. Section 2 was just a full reroof as it was the most water damaged per the reports.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I have had a better idea for how to build a spreadsheet that doesn’t require anyone (me) in the middle holding you up: a Google Form that automagically writes to the spreadsheet!

1. Complete and submit the Engineering Input Form
Screen Name
Type
Sub-type
Theory/Hypothesis <short description>
Proven Evidence
Possible Evidence Not Yet Proven
Argument Against

Tip: Check the spreadsheet to see if your Theory is already listed. If it is, use the same Type, Sub-Type, and Theory/Hypothesis so that sorting will place your entry by the previous listing. There is no limit on how many listings a particular theory may have.

2. Review the CTS Collapse spreadsheet to see your entry/entries and everyone else’s entries.

I have the input form set up to accept your screen name (thanks to all who recommended that) so that you should be able to make as many entries as you like.

We will use the Type/Sub-type fields as organizers. This will allow us to sort the spreadsheet so that related items will appear next to each other. This will be more efficient than human intervention to organize separate tabs, although we could do that after we end submissions.

Please let me know if you think any of the fields need to be updated or if anything doesn’t seem to be working properly. Have at it!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@MaudsSTL
As there is a lot of stuff located within PDF files on the Surfside website, perhaps a column where links to supporting documents can be included? Or would that fall best under the "Possible Evidence Not Yet Proven" columns?

Precision guess work based on information provided by those of questionable knowledge

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

MaudSTL

The arguments against field - we need to keep it streamlined so there aren't multiple repeated comments and sock puppets are not adding on.... etc

Wait, you've set it up so that we add the arguments to our own theory?

Also, I don't know if witness interviews can stand as proven evidence, but could be used to substantiate a theory?

Maybe make witness stmts it's own column.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented (Industrial) 25 Jul 21 19:1)

Edit: Sandblasting? Still curious how instructions this detailed for concrete repair got into the roof anchor install. Nail 2 birds with one stone?

The engineer probably made one set of plans for everything and then were later asked to divide the project up into different bid packages, that's how non-relevant specifications end up where they are not needed. It's also a good way to end up with overlaps or scope gaps. The intent though in this case was that the engineer probably wanted the contractor to perform concrete repairs (if necessary) wherever they had exposed the concrete deck prior to the anchor installation.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Could be two pallets side by side, with some rolls taken off the far one.

spsalso

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

What is the evidence that the large tar buggy was not staged on the roof. It amounts to proving a negative but... where would it be given the complaints about odor and placed away from the air handler? The reason I say this is in the tictok image I had thought there is what looks like a tow bar even before that image of the large buggy was posted late in the recovery operation. Would this help to satisfy Occam's razor for anyone? Someone knows where that thing was staged.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (MarkBoB2)

I counted 7 in each direction.

Will you number them for us?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented)

As there is a lot of stuff located within PDF files on the Surfside website, perhaps a column where links to supporting documents can be included? Or would that fall best under the "Possible Evidence Not Yet Proven" columns?

Could we use the Notes column for those links as a means to keep it simple?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

MaudSTL

Notes field for links sounds good.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

The arguments against field - we need to keep it streamlined so there aren't multiple repeated comments and sock puppets are not adding on.... etc

Wait, you've set it up so that we add the arguments to our own theory?

Also, I don't know if witness interviews can stand as proven evidence, but could be used to substantiate a theory?

Maybe make witness stmts it's own column.

We may get multiples in this first pass…we can consolidate later on if we see the need to do so.

Yes, each entry is standalone because we are not all going to edit the spreadsheet directly. In a group like this, where people don’t have actual identities, I think it’s too risky to collaborate in that way because we would have no way to prevent inappropriate editing. So if you enter a theory that you think has zero Arguments Against, you can enter None in that column. Someone may disagree with you, and state the same theory but have lots of comments in the Arguments Against column. When we sort, we will be able to see both.

I am not worried about the witness statements. I entered them to test whether the form would write correctly to the spreadsheet, and it did.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

MaudSTL

Good points. Let's see where this goes

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Notes field sounds good to me for links.

@Zebraso
Logic is the only evidence it seems.
I'm sure the people who knew where it was located have already spoken to the authorities. Inspector Jim McGuinness of all people would have known, as per his original statements, “There was no inordinate amount of equipment or materials or anything on the roof that caught my building official’s eye that would make me alarmed as to this place collapsing,”. To me that indicates he saw what was up there.
However a lot could have changed in the 14h between the collapse and his field inspection. I'm still curious was to why he's still not raised any flag over the scope of the permitted work being done as quickly as it had been, for having just gotten the permit that day.

Someone, somewhere, has to have aerial photos showing the roof in the week leading up to the collapse.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Photo source FTF 2 US&R.
https://pbs.twimg.com/media/E5U5KxlWYAMZ4Rc?format...
The 8th floor slab has failed differently, possibly with some hinging. Just an observation. Would this give us anymore insight into what we see with the floor above 711 shifting before the full collapse?
This would also be roughly where the family from 904 reported falling to the floor below and staying there briefly (long enough to crawl) before this floor gave away.

What would make this floor fail like this compared to the rest? I cannot wrap my head around it.

We have the 8th and 7th floor photos of the non collapsed section here.
Edit:https://res.cloudinary.com/engineering-com/image/u...
https://res.cloudinary.com/engineering-com/image/u...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Maybe the 8th floor slab had a wee bit less rebar at its top in this area.

spsalso

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Demented,

This is the interior view from 705

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Partial roof area #1 15,496 and #2 1,711 sq.ft = 17,207 sq. ft. for the gray areas. (from preliminary-review-plans-for-40-year-re-certification) called for CCW-500 hot-applied liquid waterproofing membrane.

Two layers, I estimate 15,275lbs for 125-mil coating, plus 10,992lbs for 90-mil, plus 200lbs of felt. Total around 28,267lbs. That's 584 blocks or just over 9 pallets. Plus a little for the felt/fabric for those two roof areas:
CCW-500 Reinforcing Fabric 24lbs/roll good for 2,000 sq. ft. 9 rolls x 24lbs = 206lbs.
Durapax tar-saturated 43 rolls X 60lbs = 2,581 lbs. I'm not sure if this is the old roof material.

The mass of the required roofing materials is significant, stored on the roof and on site somewhere?

I can't see them constantly bring the crane on site to lift more materials to the roof. It was a rush job to start late, rainy season coming.

In the debris it looked like a smaller kettle trailer (single axle?), maybe 150-200 gal which would weigh 1,700-2,300lbs of materials plus fuel and the trailer's mass.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@Optical98. I think we can see the location of the tar trailer here. Middle of frame, at the back. It does not look like it to me, but lost pixles being lost pixles, Not sure what sense it would make being in this location other than it having been moved from it's found location in the cleanup.

Could this also be the approximate size of a counterbalance weight some have speculated about? Edit: Job boxes. Why do I always forget job boxes. They're big, square, sturdy, and often tan, orange, or brown. Lockable, heavy, and full of tools. Perhaps even the external supply tank for the generator, but that would be amazing for the fuel tank to survive.

https://youtu.be/jI6Up5Nv70c?t=249
Video at time. 3:58.

@Lucky555
Cranes were not constantly scheduled. So roofing materials would have been initially stored on the roof, or carried to the roof by hand/dolly via the elevator if stored at lower levels. I'm curious if concrete and epoxy were stored up there as well for the repair work that was OK'd to go without permission so long as it wasn't so bad it needed inspection/engineering.

Edit: To spark thought. *shrugs*
https://www.latimes.com/archives/la-xpm-1993-03-11...
https://miami.cbslocal.com/2019/03/06/tar-kettle-s...
https://www.local10.com/news/2017/04/24/big-lots-e...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented (Industrial))

other than it having been moved from it's found location in the cleanup

And NIST has those images I assume. Good job on finding that video. I was looking for that.

Edit: The thing with that particular item is it does not match up to well with the photo of the tar trailer that was seen placed with the smashed car. Not saying it can't be a tar trailer or a job box.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Spartan5, here is my count of tarpaper rolls. I preferred to use my figure instead of the one you provided because mine showed them in a perspective view instead of a straight top down view.

I can count 30 rolls that I can see, with 25 of them on the two left-hand skids. I assumed that the two right-hand skids carried approximately the same number. Some are covered with the bag and some have been used already. I found out that the symmetry was more like 8x6 rolls rather than 7x7 rolls.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Good eyes Demented, that looks like the same area as the unburied version looked to be.

I don't know if you've watched this video or not, but they really put a lot of focus on this white vehicle. Which reminded me of our discussion on the CRV yesterday....

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

The 2017-2020 MDX? Yeah, I noticed it. Early morning hours, around 6:50AM-7AM that day they lifted it out. That's all I know before I had to leave for work that morning.
They were passing cars along with excavators to that spot to lift out. An assembly line of sorts. I do believe this was parked under the demo'd building, almost on top of a curb, on the top level of collapsed decking.Edit: Looks like I believe wrong.

Edit for below: Yes Thermo, Honda/Acura the same.
All hail our SAE overlords.

I think I need to go back to that world. This south Florida structural stuff scares me. Any engineers/inspectors in the area, spend a week working with a staffing firm looking for construction laborers in the area. Let the people work around you when you don't have the clipboard and badge out. They act a whole lot different around you when they think you're one of them. You'll learn a lot in just a week, and it'll help us keep stuff safe.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Demented can correct me if I am wrong, but the Logo on the Wheels of the potential white SUV is an Acura Logo, so a Honda Product

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I found a copy of the surveillance video showing the collapse of Champlain Tower South that has much higher resolution than all other videos. It clearly shows the wall on the roof between the penthouse roof and the normal roof. It also has no blooming of the lights caused by saturation of the camera viewing the original video. This provides a much better understanding of what happens on the roof during the first few frames. It has caused me to reassess my labeling of the floors that collapsed first, which changes what one thinks happened to the penthouse roof.

The video can be found at: https://www.today.com/video/why-did-florida-condo-....

By copying several frames from this video into a PowerPoint document, one can click on the thumbnail images on the left in the document to simulate how the video operates as well as stopping the video and going back and forth between two frames to see what has changed. I tried to attach my copy of a PowerPoint document to save everyone some time, but the upload operation barfed and twice rejected my uploading.

I hope that this video will aid everyone in their understanding of the surveillance video.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Ok now on this pic, zoom in to the right of the blue tent as far as you can

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (MarkBoB2)

I can count 30 rolls that I can see, with 25 of them on the two left-hand skids. I assumed that the two right-hand skids carried approximately the same number. Some are covered with the bag and some have been used already. I found out that the symmetry was more like 8x6 rolls rather than 7x7 rolls.

Wow.

There are 4 rolls in the front course. You have labeled/counted them 11 times (rolls [1, 2, 7]; [5, 6, 11]; [9, 10, 14], and [13, 30].

There is no right hand skid. There are a few rolls that tipped off the skid in the foreground.

Is anyone else seeing this? One of us is in crazy town.

I move that we add this picture to the spreadsheet and have everyone count the number of rolls of tar paper that can be seen. This will provide a measure of credibility to the various theories/interpretations.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

Ok now on this pic, zoom in to the right of the blue tent as far as you can

Not a Honda/Acura. Is that a Porsche in the pool?

Edit: Yup. https://www.motorauthority.com/news/1127739_2023-p...
I remember people talking about it. Cars with leaking fuel were put in the pool if I am not mistaken. There was an issue with the recovery igniting fires once they got to the garage level because of fuel leakage. Other than here, I have seen/heard nothing about a car hitting a column, if thats where this is headed.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Are we really going to argue whether there are 20 or 30 rolls of tar paper on a pallet?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I think I can pinpoint the location of that white MDX, or at least offer a point of reference that helps us find the location of the camera within the site. Assuming many things (it was not moved, parking spots did not change):

at 0:07 of the video you can see the front clip of a 2000s Ford Expedition, with an aftermarket bumper guard

The exact same vehicle is visible in the walkaround of 611 just before they reach the ramp area:

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Well that's interesting.

@Optical98
And an additional 10 rolls is 600lbs and very relevant to the idea of it being used to load test a newly installed anchor.

Precision guess work based on information provided by those of questionable knowledge

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

Are we really going to argue whether there are 20 or 30 rolls of tar paper on a pallet?
Probably not in this thread. WAGs rule the day.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Demented, not sure where they pulled it from, it doesn't look as crushed as many we've seen tho.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Looks like same Ford Dealer Tag in walk thru

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Hey hey hey, no name callin Spartan5 >.>

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

If you crash into K4 with a car resulting in failure, could upper slabs fail due to a a redistribution of load following I, H, and E, leading to the PH roof collapsing as it now meats the shear wall and begins to tear cleanly and dropping roofing equipment on the pool deck, causing the deck to collapse and generate even more load redistribution but now with hinging on the pool deck, causing the now un-collapsed front section of floors Basement up to 8 to collapse, with a pause between front to rear due to a collapse with middle portions of slab between the N and S sides and it needing to catch up, now leaving the East section standing and wobbling badly before losing it's fight with Newton?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented)

@Optical98
And an additional 10 rolls is 600lbs and very relevant to the idea of it being used to load test a newly installed anchor.
vs tying off between two anchors and using them to load each other. As we determined elsewhere in the thread.

These rolls are most central to the cockamamie idea that rolling tar paper burst through the parapet wall after the roof partially collapsed due to hammer drilling for Hilti bolts for roof anchors… said tar paper rolls then plummeting to the ground with wayward ac units and tar buggies, crashing through the patio deck ultimately causing the collapse of the entire building. Don’t you remember the tar paper rolls being identified in the TikTok video of the garage collapse?

Pretty sure it’s the same people that could see 7x7 rolls on that pallet as would attest that they can see them in the basement as well.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Well maybe the AI software that someone used before could fill that pallet out? Give you a more accurate count?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@Spartan5
Oh I do agree it's silly and stupid. What roofing crew are you going to find that's going to lift a 2,000lb pallet over a wall and drop it? Yeah, good luck with that. You'll find that just as easily as you'll find a day crew in FL that does not have at least 2 come alongs on the truck and 10 on order with Merchant Metals or Wurth. If anyone is going to load test it, it's not the workers, it's going to be 1, 2, or 3 of the SI's doing it on site. You can't even trust the $10/h laborers to read a tape measurer accurately, let alone know what load testing is. Skilled labor is hard to come by these days. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Ok well, when you put it that way Spar..... Did you read about my Fire hypothesis? ^^ ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Spartan5, If those Hammer Drills damage what little negative moment rebar is available over columns and developed say only a short distance into slab, that is a much bigger problem than you want to admit.... I would appreciate you offering up your theory on MaudSTL's Database. I think it is a lot more constructive for us to cite our theories than throwing darts at each other....... I can easily see more rolls of tar paper than your count, but perhaps not as many as others.... It really does NOT MATTER.... ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Spartan5 "Don’t you remember the tar paper rolls being identified in the TikTok video of the garage collapse?" Um no, I was still trying to conceptualize the planter box falling thru rebar and landing perfectly intact... honestly I thought it looked like a washing machine ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 The rolls are arranged in staggered rows to achieve efficient packing, so 5 rows of 5,4,5,4,5 making 23 all together. There may be a few loose ones under the green tarp. If this is anything to do with the collapse of an ostensibly professionally designed and constructed RC building in a first world country I'll be....surprised ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 @Thermopile That game is fitting for what ever the cause is. This building was just bandaids holding hands. An unfortunate chain of catastrophic events over 10 minutes could have easily undone the "beautification" work all over the building. I'm still more inclined to believe heavy rains added too much of a load onto the crumbling deck that was holding water, as well as a clogged retrofit French drain in a planter that had it's original drain holes filled in under some permitted work. But I've seen too much evidence of wankery on this building due to poor management by a cheap-ass condo board and a crappy workforce, that to me indicates that this building, although built in the US of A, was slowly transformed into the sort of third world country building that we would not be surprised to see collapse due someone having slammed their front door a little too hard. Too much gravity in one spot. I'm pretty sure after all that's been seen, no one is surprised this building did collapse. It's like a game of Jenga that 34765460384560286534 different engineers and contractors decided to jump into, but along the way they kept modifying all the pieces with no concern to what any other party has done in the past, or was going to do after. Check the original plans and work off that. All will be good. Surfside's record keeping doesn't seem to be the best in the world either which I doubt made accurate engineering to the structure all the more difficult. Either way, I am interested in knowing if the collapse could originate in that path. I see no harm in combining everyone's theories into one event. How else would we fill up the 10 or so minutes of collapse? I'm sure the NIST lasered every inch of that pile and marked out what was on top of what. Oh the years of waiting. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (Optical98 (Computer)) 26 Jul 21 02:30 Well maybe the AI software that someone used before could fill that pallet out? Give you a more accurate count? You mean less accurate. The moment I use the AI software, it ceases to be a photograph and becomes a digital painting. A *very convincing* digital painting, but still not a photograph of what was actually present. The same thing is true of *any* interpolating enlargement. If this were a court, it'd be evidence tampering. That's my whole point with showing it: you can enlarge images, but it doesn't get you any new data. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (MarkBoB2 (Electrical)) the surveillance video showing the collapse of Champlain Tower South that has much higher resolution than all other videos On the Today Show video I cannot find any hint of a parapet. You would think if it was there the clearer video might at least show a hint of it. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Eufalconimorph, Ok, I thought if you just gave it one roll as the model and told it to multiply by x & y margins it might work. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Moot point, but the green crane hoist bag with yellow handles on the roofing rolls is not a tarp. FYI ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Demented, I'm enjoying the many theories and such retorts as "cockamamie idea that rolling tar paper burst through the parapet wall!"... have me rolling. I am on "Team Trigger" tho, I can't (don't want) to believe a building like that can just vaporize one night. That's a terrifying concept with so many condos within those same margins all along that coast and others. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Oh it has me scared too. I'm not looking forward to going to work tomorrow. I have to continue fabrication on some Bahama shutters being retrofit to some columns on a PH suite somewhere on the ocean. I have my doubts that any engineering on windload was done, let alone on if the placement of the 2-3/4"x1/4" 308L (this rusts on the ocean. I don't know why we use it) tapcons. The fabrication matches nothing with the drawing thanks to a foreman who does everything in his power to save the boss a dime on labor to account for his shortcomings in ordering the incorrect, but more expensive material or not knowing the difference between 3 and 4. So not like engineering would have even mattered since this thing is now more than double it's original weight and the weldment areas have gone from .093 to .125 open corner and fillet welds to .093 to .375 fillet and .25 to .375 double v. 2024 to 6061 with 4043 DC MIG being heat-washed over with AC GTAW for some reason. There is no hero award for trying to always be the nice guy. I either do what I'm told because I like having a roof over my head and food in my belly, or I walk away and hope I can land another job that day. Even reporting to the Miami OSHA field office is a joke. In the 10 years I've been reporting issues because I take Safety serious, I've never seen anything more than a slap on the wrist, even for serious and potentially fatal if not rectified issues. You know they call the employer and give them a heads up before the show up right? Precision guess work based on information provided by those of questionable knowledge ^This tag line isn't because of engineers. Before Covid, my fabrication and maths was under the scrutiny of 3 and 4 letter agencies constantly. I've seen some stuff recently that's haunting. They joke about how it's not going to space, but when you fire back "this is why building's collapse", it falls on deaf ears. Ignorance truly is bliss. The men that build the stuff where we sleep often don't care, because that's not where they sleep, and it's almost quittin' time. Is it Friday yet? ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 One last thought for evening. If the concrete is as bad as it appears, I can easily see hammer drilling to cause break up in places of concrete, causing the need for larger repairs before mounting OSHA tie offs. Now could be the workers just throw in some extra epoxy and called it good, since anchor plate would hide the problem..... I think folks need real hands on field experience to fully understand what actually goes on.... It gets me started on how I have no respect for someone that has not come up thru the ranks the hard way, because I know they can not grasp everything, without having that experience. It is like the company bringing in a English or History Major as CEO of an Engineering and Construction Company.. Sorry this hound does not hunt!! You can not manage stuff you don't under stand..... IMO. The more diverse hands on and book knowledge and skills you have, the more capable you are..... I know PhD's that I would NOT let touch an electrical panel for example. They may blow me away on book smarts, but they are at a loss in the real world at times.... ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (Thermopile (Aerospace)) You can not manage stuff you don't under stand..... IMO You are echoing the father of the nuclear Navy, one Hyman Rickover. One story is that he turned down an applicant because he put salt on his food before tasting it during the interview. Edit for spelling the Admirals name wrong. Oops! Also: “Sit down before fact with an open mind. Be prepared to give up every preconceived notion. Follow humbly wherever and to whatever abyss Nature leads or you learn nothing. Don’t push out figures when facts are going in the opposite direction.” ― Hyman G. Rickover ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 (OP) #### Quote (Optical98 (Computer)26 Jul 21 01:55) Ok now on this pic, zoom in to the right of the blue tent as far as you can OK, Yes, there is a crushed car. Now what? SF Charlie Eng-Tips.com Forum Policies ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 SF Charlie, We were noting the various crushed cars being pulled out of the site with cranes, they swing them way over to the back to be hauled away, but I was wondering why there was this one car sitting alone in the pool. Demented said some would catch on fire when being pulled out, so the crane would just put them in the pool. I suppose it had water in it at the time. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (MarkBoB2 (Electrical)) I found a copy of the surveillance video showing the collapse of Champlain Tower South that has much higher resolution than all other videos. Well, I felt most of us already saw the penthouse roof shape in the original Twitter video... The TODAY video is just a reproduction of the same phone recording that WSVN published, but zoomed in slightly and color adjusted. I think the dead giveaway is that you can still hear the "botanical gardens" music in the news report. Still, I took snapshots of both videos trying my best to match an exact frame, have a look: They basically made the video look warmer and blew it up a little without adding data. Original source links: https://www.today.com/video/why-did-florida-condo-... https://twitter.com/wsvn/status/140805404680880537... ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 3 #### Quote (Optical98) I am on "Team Trigger" tho, I can't (don't want) to believe a building like that can just vaporize one night. That's a terrifying concept with so many condos within those same margins all along that coast and others. Triggers? Sure. There’s a chance of that, or of general decay or of non-compliance with the original design. Probably all three. There are the “curious” concrete samples after all. And the unusual punching failures in the ground level slab. But I’ve not seen a single conclusive or tangible piece of evidence regarding anything being initiated on the roof. Not a one. It’s all been loosely supported conjecture at best. And otherwise imaginations running wild at worst. I mean… we have talk of 3/4” hammer-drilled holes taking out reinforcement. Or somehow vibrating the entire thousands ton build so that it shook the patio slab loose (many hours later). We could come up with dozens of hypotheticals for why the roof could fail. But to what end? There’s nothing indicating that it did. Never mind the core samples, where the preliminary failure is known to actually have occurred, that went clean through the rebar in several places. Tonight, I saw 4 rolls of felt get transformed into 11. It’s just too much sometimes. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 2 Youtube - Structural Madness An excellent engineering review of the structural shortcomings of the pool deck level and building columns. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 8 If anyone from the general public wanted to get a flavor of the structural engineering community's theories and discussion related to the Surfside collapse, God forbid they stumble upon the last couple iterations of this Eng-Tips thread as a source of education and insight. At the hands of a select and persistent few, the discussion has turned into Grabassery 101, rooted in some of the most biased and inane "photo-analysis" conjurings and subjective babbling one could dream up. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 I have to go back a bit to the comment that image enhancement constitutes somethin akin to evidence tampering and would not hold up in court. That is patently untrue. In fact it is a legit forensics technique which has been used to obtain murder convictions that otherwise would not have been obtained without it. I hope that is clear enough. Also the notion that image enhancement creates data that was not there by altering the original is untrue. NASA has pioneered image enhancement for the purpose of scientific research of deep space. They are not reaching false conclusions on that basis. You can even get some of their algorithms in free/trialware and mess around with it. There is also a photoshop plug in for it if I am not mistaken, but you have to pay. In the case of Sharra Ferger as long ago as 1997, Lucis (Nasa image enhancement) was used to clarify a bite mark photo and clear the wrong suspect after he was convicted and sent to prison. The same enhanced image was then used to identify the correct suspect and along with his DNA to convict him. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 3 #### Quote (Seppe (Structural)26 Jul 21 07:21) It would not be a significant loss if these threads were deleted entirely. Nothing has been learned that isn't covered better elsewhere. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (Demented) I am just curious if this is, what process would have been done to leave this shape of a mortar patch? They're too uniform for it to be by hand one would think. Would a template be used in this process? Ooooh look at all those repairs, I bet those beams are like Swiss cheese on the inside. Actually, it looks like those are simply imprints of the patches that were used to fill the knots in the plywood that were used for the forms. When you’re a hammer, everything looks like a nail. When you’re an unsupported theory, everything looks like evidence. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 As I said, it was a question to the method. If we get attacked for asking questions to something we don't know now, then there is more wrong with this world than I thought. Thank you for answering my question though. If those were repairs, they held up good. Would have been pretty damning evidence against concrete repairs. Precision guess work based on information provided by those of questionable knowledge ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 2 #### Quote (Demented) If we get attacked for asking questions to something we don't know now, then there is more wrong with this world than I thought. In the context of at least 1,000 posts of pure uninformed conjecture, people are going to get testy with basic questions like these. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 This black area the red arrow is pointing to is troubling to me. It looks like part of the very large PH balcony has fallen and we are looking at black roof in this area and not vertical PH parapet. Hinged slab near sliding door wall. No a 3/4" masonry bit in a hammer drill is not going to take out 1/2" or 5/8" rebar, but it could kit and glance off bar and break up what little concrete bond there is between rebar and suspect concrete such that it renders the short poorly developed steel from proving any say negative moment capability. You know when you hit steel with masonry bit, so what do lots of workers do in this situation, they tilt the drill a little bit and keep drilling past it.... Problem is they have to tilt it perhaps more than one way to figure out which way the rebar is running, all the time they are hogging out the 3/4" hole much larger and detaching or delaminating the rebar from the concrete..... ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 I would like to point out, after all the postings here, it was Building Integrity's Video that came up with delamination theory, and not any of the Structural Experts on this Forum. Perhaps the experts on this forum already knew that, but was just holding back their theory? I would like to also say a lot of the structural expert analysis is based upon a perfect world and the original design drawings, and NOT the as-built configuration that we really know was not as designed..... Let me also say, if I were a practicing Structural PE, I would be going by the book too in my analysis as I would not want any liability from speculation. However, for the non-PE types here there is no risk to exploring concepts based upon the real world facts and best public information available to date as to current condition of building, and not brand new design condition of perfect world structure.. If the pool deck slab at the planters next to building failed first, then the core sampling of the slab (Core A) in that area, probably contributed a lot to the sudden failure coupled with heavy rain loading that area after recent loss of a steel rebar continuity while probably causing more delamination in that area... ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (Demented) Question for concrete guys. Would this be indicative of a column repair location? I am not concerned with the cracking as I wouldn't be surprised for this to be related to the removal. I am just curious if this is, what process would have been done to leave this shape of a mortar patch? They're too uniform for it to be by hand one would think. Would a template be used in this process? Since they appear shallow and aren't broken off, my vote would be for knots in the plywood formwork. These would be limited to a single-ply depth. The roughness of them further advances this theory in that the inner plys of plywood aren't sanded smooth before gluing. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (MaudSTL (Computer)26 Jul 21 14:59) Included in the video is a 3D view of the TikTok view into the parkade which makes clear how the column line recedes into the shadows. The large grey block sits in front of the missing column while the upper portion, if not obscured by a sagging deck would be dimly lit to the point of being faded out. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 @MaudSTL this is a nice video. His explanation nicely summarizes and illustrates the pool deck collapse theory. I did not realize that the east stairwell shear wall ended up flopped all the way over to the west. Edited post to remove the suggestion of a "pool deck theory". The video explains the likely mechanism of the collapse well. Discussion of the triggering event is not part of it. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 @Thermopile I'm sure you've seen it when those same people drill the same way in steel structures. Oooof. You can feel the building vibrate as they do it. The angry angry chatter of interupted cuts and the vibrations associated with. Just kicked back a bunch of cnc work because it chattered like crazy in the wooden jig with 3.5" unsupported stickout on thin material. Why is the woodshop machining metal? I don't know, but we renovate condos. Precision guess work based on information provided by those of questionable knowledge ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (zebraso (Mechanical)) it is a legit forensics technique which has been used to obtain murder convictions The type of enhancement is critical. Knowing the context of an image or video and the mechanisms of each enhancement is part of being a photo forensic analyst. Otherwise one could generate highly misleading pictures by blindly using the same tools the professionals use. In recent years AI-based enhancement has begun to add data to pictures... even a layperson nowadays should be especially careful about media from untrustworthy sources. #### Quote (Thermopile (Aerospace)) This black area the red arrow is pointing to is troubling to me. It's an artifact of taking a video of an LCD screen. The missing white up top is compensated for by the missing black right below, indicating the LCD was in the middle of a transition. The detectives must have the original feed and just haven't released to the public. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 @Demented, yes during college, I worked in machine shop and welding shop, designing, fabricating and installing creative field repairs. My dad's contact's got me the job, but my open mind and aggressive desire and ability to learn coupled with baseline skills and work ethic kept the job for me. In that time, no engineering designs to work from. It was a different era. Mostly supporting manufacturing plants and facility and equipment repairs. I had read the Topic of this Thread is Forensic Engineering with a sub-topic of Engineering Failures and Disasters. How does this limit this forum to just talking about pure structural design criteria stuff without considering real world forensic pieces of the puzzle? PS: No engineering disasters from the work I did.... But plenty of margin.... Auri, thanks for that response. I realize everything may be there in the poor quality edited video we have, but something just does not look right about the middle section vs the right section near the top.... Demented, got any old Monarch Gear Head Lathes in your shop? Built to Last forever with maintenance and repair.... No Buggy Software either....or a Vintage Lincoln Buzz Box? ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Not sure if anyone tried this already, but I tried to create the same angle in Google Earth as the security camera footage of the collapse. It's pretty clear that the middle part of the building has already dropped about one story at the beginning of the video. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 What a good interview... (incognito if you have to) https://www.palmbeachpost.com/story/news/2021/07/2... Vach almost makes it seem like we handled the concrete debris and they handled recovering the people. I hope we were as meticulous about labelling the column/slab pieces before transporting to Doral. It would greatly help diagnosing any internal building failure as a suspect cause of the plaza collapse. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (CE3527) Not sure if anyone tried this already, but I tried to create the same angle in Google Earth as the security camera footage of the collapse. It's pretty clear that the middle part of the building has already dropped about one story at the beginning of the video. Yup, and it's basically the entire 10 & 11 stack that has dropped (on the facade / south span, at least), in a bottom to top collapse. I can't be certain, but I suspect the facade has been pulled slightly inwards / northwards by the slabs hinging down at about the 4 line / central corridor (maybe briefly resisting on the 8 line before reaching 4). It also looks to me like the master bedrooms (left side) of the 12 stack are fully involved in the early stage of the tower collapse, with the M–N span hinging downwards on the N columns. It seems quite clear to me that the opening frames of that video clearly show catastrophic failure in the 9.1 line, with I,K,L,M gone somewhere low down, probably starting at the ground / basement level. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (CE3527 (Civil/Environmental)) It's pretty clear that the middle part of the building has already dropped about one story at the beginning of the video. Yes, but then some way back in the thread parts questioned whether the roof had collapsed (or hinged) initially before what was below it started moving, which could be dismissed easily if the video started about 1 frame earlier. And then someone wants to know how the lights are still on below if all floors had progressed 1 or so levels downward. And it goes on from there. I think Building Integrity lined up the architectural features in the eastern most section with the floors under question to tell if the roof had progressed before the rest. I right now for the life of me I can't even recall what he thought about it. Edit: Ok Building Integrity does not believe the roof dropped or hinged first. But what he shows in his diagram "hinges" somewhat on whether the line he draws for the top of the penthouse is actually the leading edge parapet wall or the back edge hinge line where what you are seeing as the PH level (it's dark) is actually the top of the roof. So: grainy image. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 I truly hope MaudSTL will contact her friend in Israel, as they probably already know the real truth. Look how fast they generated a model and found bodies, and got out of dodge. They have lots of experience with collapsed buildings in their neck of the woods... ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (Auri (Bioengineer)) The type of enhancement is critical What you are saying I agree with. You wouldn't want to use the standard type used to enlarge a family portrait. There you would have the intent of smoothing details to eliminate grain. Instead you would produce a grainier image while enlarging which is counterintuitive to photography. The problem here is the originals are not forensic quality to begin with. In the case I cited there were two subject matter experts (forensic odonatologists). The one that analyzed the enhanced image reached the opposite conclusion of the one that examined the unenhanced image. There is a difference between pure speculative folly and forensics of course. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (Thermophile) I truly hope MaudSTL will contact her friend in Israel, as they probably already know the real truth. I contacted my Israeli friend just this past week. I specifically asked her to see if she could find and translate the Israeli Channel 13 interview with Gabe Nir. I have been hoping Gabe might provide more details in a Hebrew interview. Anyhow, my friend hasn’t been able to find the interview so far, but she’s going to keep looking. I’ll report if she tells me anything else. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 2 #### Quote (Thermopile) I would like to point out, after all the postings here, it was Building Integrity's Video that came up with delamination theory, and not any of the Structural Experts on this Forum. Perhaps the experts on this forum already knew that, but was just holding back their theory? Or perhaps not every poster here is as compelled as you and a couple others seem to be when it comes to throwing every strand of woulda-coulda spaghetti against the wall to see what might stick. This isn't a competition to see who is willing to dig into the bowels of minutiae just for the sake of a water-cooler talk. I'm not at all opposed to the sharing of thoughts and ideas, but I also think there's a point in time where, as folks who weren't on the ground as part of USAR or NIST deployment, we reach a reasonable limit on just how accurate and productive a belabored attempt to analyze/assess can be. Speaking for myself, I reached that point about four or five thread iterations ago. I continue to believe that this structural failure was the result of a series of compounding, unspectacular issues at the pool deck level. I don't think the confluence of these issues and the degradation and resulting destabilization needed to have an acute vehicular impact or "butterfly flaps its wings in Brazil" roof-level sequence to be considered legitimate and plausible. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (MaudSTL) South African Architect Mike Bell has published a new simulation with narration. https://youtu.be/2INrz2u9-sQ For those who won't open up YouTube to watch the video. Btw, you should; it is short, but packed with good visuals. I think this simulation of the collapse agrees well with the security cam video, without the need for a collapse starting at the roof area. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 @Thermopile, Sadly no. We have an old clapped out Bridgeport lathe with no dead man's pedal and a Vectra knee mill that is essentially a fancy drill press in this shop. M-I-C, K-E-Y, M-O-U-S-E. I've done some pretty far out there set-ups to get jobs done with a lack of tooling. The man in charge of the shop is an artist who after cutting it twice and it still being short too many times, has finally learned to cut it 5" to long and trim it to fit the .9:1 print he printed out on the big printer using the surface plate as a work bench. I gifted my vintage Buzz Box to a new welder a few years ago. That thing got me my start on Al GTAW. Those AC only Buzz Box's still are some of the best transformer welders. After 20 years of dragging it along in moves, enough was enough. @BadgerPE Thank you so much. @Seppe Pardon me if you think it's all just silly conjecture, watercooler talk, and spaghetti against the wall. For my crazy ass speculations, as far as I am aware, I've done my very best to disprove more of my own stuff than anything else. Sure, I'd probably be more in my element if this were an exploded or crashed airframe, or a vessel that sunk, but having seen what I've seen due to craftsmanship flaws, at least in my own sense, I know it's not a waste. If anyone thinks any agency that is going to be directly involved in the investigations is NOT going to dive into the past of the building before the collapse to come up with suspect areas to check, you're simply foolish. We cannot simply go "Well, the building fell down because the design would have made it come down if the deck collapsed". https://www.nist.gov/disaster-failure-studies/data... Why did the remaining structure not collapse? Better question? Well for one, I know there was an absolute ton of jack-leg work done on the ocean side of the building, but the work done along Collin's Ave is vastly different in everything from it seems quality, buiding materials, inspection, and permitting. I'm fairly certain I'm not the only one who can see how sections of the building would not resist collapse or additional stress due to failures of past contractors and poor, or no, engineering to modifications. In an ideal world, we'd hope that one column is not what it takes to bring a building down. But in a world where one column may just be able to bring an entire building down, there is only harm in refusing to look at other contributing factors. I still do not understand how people can model a building off of what we know is, as per a lot of the as built we see, off of simple speculation that nothing out of the ordinary is going on. We know 100% this is no ordinary situation. It's like a rocket surgeon insisting that the Challenger disaster only happened because of a lack of an escape system. Bad analogy, but I know some will understand. This building wasn't OEM. I may be insane, but at least I'm not the one insane enough to scribble on a contract/permit for the pool deck to use smooth 305 stainless rods in place of rebar. So you want to talk about the decking that collapsed? I'll gladly jump back to hundreds of tons of added water on the pool with clogged drains and faulty construction. I'll even dig back in for the photos of and emails of complaints of sand and styrofoam clogging drains in the garages and pool decking thanks to changes in Surfside's beach access policies and even issues of dump trucks of sand using portions of the underground ramp to turn around during an ACoE project. I don't have any form of maths on the vehicle weight, but I'm pretty dang sure that's a little overloaded. Anyone ever put any thought into why we see so much upper spalling? This sort of deviation from standards and plans should not be brushed off as nothing. There is no doubt in my mind that if people's models were modified to include the known as built vs the as design, that pool deck collapse would be far far easier to happen than any of us all can even grasp. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Choose the Right Synonym for badger Verb BAIT, BADGER, HECKLE, HECTOR, CHIVY, HOUND mean to harass by efforts to break down. BAIT implies wanton cruelty or delight in persecuting a helpless victim. baited the chained dog BADGER implies pestering so as to drive a person to confusion or frenzy. badgered her father for a car HECKLE implies persistent annoying or belligerent interruptions of a speaker. drunks heckled the stand-up comic HECTOR carries an implication of bullying and domineering. football players hectored by their coach CHIVY suggests persecution by teasing or nagging. chivied the new student mercilessly HOUND implies unrelenting pursuit and harassing. hounded by creditors ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Hector. *fingers crossed for a gold star* ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 All that tar paper piled high on the part that DIDNT collapse. Thats the cause right there. Please expand on this theory. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 But we can go, the building fell down because the design made it fall down if the deck collapsed. It may be the "it's just a pool deck" thinking that led to the maintenance not being taking seriously for 40 years. If one of the condo units had cracks, water, and rust dripping into it, they would have jumped all over it. What was likely overlooked by everyone, and not surprisingly since it was unprecedented, was the danger the deck posed to the building. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Based off of the emails with the consultants and condo board to the town of Surfside, they were indeed VERY desperate to begin work on the full slab replacement ASAP. They didn't care about costs, they didn't care about time, they only cared about additional parking off property so that construction could start A-FUCKING-SAP. But town officials stalled. It seems in fact they very much wanted to get this done right this time, finally. They've been screwed over by so many bad contractors that it ballooned the prices so astronomically high, I cannot imagine they wanted to risk doing this all again in another 5 years. This "it's just the pool deck" thinking wasn't their thinking it seems from everything that's been put forth. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 While jumping all over the bozos who worked on this building for 40 years is not unreasonable, hold back something for the architect, the engineer, and the general contractor who built it in the first place. Plus a dab for the building department that missed it all, while it was being built right in front of them. spsalso ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 Unfortunately some of those who have a lot of the blame are already taking their dirt naps. It doesn't stop my outrage at them though. They're just not the only at blame it seems. Edit: I don't know about other states, but damn man, Florida didn't even ban driving with open containers in your hand until 1988. Construction crews run on 2-stroke. Yuengling-ling-ling-ling-ling-ling Edit again: Crap, when did this state learn to acnhor roofs down on single family homes? 1992? Edit: Ever stop at a gas station around 12PM, go inside, and wonder what the guys in the yellow shirts and the beers in their hands do when they go back to work? *Sings along to Lesley Gore* ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 While the "South African" video is quite good, I also recommend the video that Sym P. le volunteered: https://www.youtube.com/watch?app=desktop&v=fF... I thought it had a lot of good comments, while still being understandable by a Sparky. He did good. spsalso ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 2 98 is a lot less than 161. That's great news that so many weren't there who might have been. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 The building might have been poorly designed and built, but it stood for 40 years, and onus of repairing and fixing any issues or faults lay with the owners. There were plenty of signs of problems. There were measures they could have employed to work out if the building was safe. The default of the building being safe unless things are falling down, seems to the assumption. Perhaps with products, we should be working out "when is the end of life" for a product. 7 years seems to be the best before on plastic parts in the automotive industry. Is 40 years end of life? ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 The Structural Madness video is pretty good: a detailed analysis indicating the pool deck was on the brink of collapse and that the connection to the building at the step compounded matters. Does not cover later insults to the fabric like the core holes and the delamination but otherwise good I thought. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 #### Quote (AutisticBez) Standing for 40 years is not itself a qualification for standing another 40 if the accumulated flaws and faults over that time played directly into design and construction imperfections that in combination create conditions for a more sudden collapse than engineers' experience leads them to expect. I agree completely that delayed and cosmetics-focussed maintenance was an issue, but if the prevailing wisdom was that a structure in terminal peril will express itself before disaster I can see why human nature took the path of least resistance. I believe there will need to be a specific inspection regime developed for similar aged/design structures that looks for weaknesses from age and accumulated misuse, and probes critical structural connections for integrity, steel content, etc. Edited to add: there seems also to be scope for more legislated carrot and stick mechanisms for encouraging owners to undertake heir own structural as opposed to cosmetic inspections and improvements, perhaps by a scheduled depreciation of buildings that do not comply. Good luck with that one though. ### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09 How is concrete infinitely repairable? Multiple repairs were hammering out spalled concrete, sandblasting rebar and then fill with concrete and oh look at the lovely cold joint. I can't see the strength in "repaired" columns. Original construction contractor Edward L. Nezelek Inc. sure has a track record of shoddy work and so many lawsuits. He seemed to think everything was an extra charge or was a true rat. This (1981) sound familiar, just like Coral Gables? "Gesco filed suit against Nezelek alleging breach of a condominium construction contract and sought damages for alleged substitution of inferior materials, defective construction and delay in completion. Nezelek denied these charges and asserted several affirmative defenses, among which was a claim that Gesco was solely responsible for the construction delays. Nezelek also counterclaimed to foreclose on its$1,117,614.92 mechanics lien which represented the alleged balance due under the contract..."
"Another dispute concerns damages resulting from defective construction of the condominium's parking deck. Gesco claims that Nezelek's failure to follow its specifications resulted in a leaking deck, and that in addition to the alleged defect in the deck, that this leakage also damaged cars which were parked below the deck. The parking deck was made of concrete. Concrete, as noted by the trial court, is a porous material which will crack and allow water to leak through. Gesco was well aware of this fact. Its own consultants advised waterproofing the deck. Nevertheless, Gesco elected not to do so. Therefore, the fact that the deck did crack, allowing water to leak through, should have come as no surprise to Gesco. Having ignored the warnings of experts as to the consequences of failing to waterproof, Gesco may not now recover the expense it incurred in reconstructing the deck. It is interesting to note that upon this reconstruction, Gesco employed the very waterproofing technique which it rejected initially. Gesco's other allegation concerning premature "shorring" by Nezelek is unsupported by the record. However, the record does contain evidence that Gesco may have contributed to its own injury by using heavy equipment on the deck.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented (Industrial))

Florida eh. So yeah, a scooter inside is possible.

An O2 tank would complete the picture.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

"Maybe the media is not accurately reporting what he said."

That's why they're Not "witness statements"

sox..

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

For line 6 in your spreadsheet the time should be ~11:30PM according to that article you referenced in line 4. FYI.

Thanks for finding that…will correct.

We had a big discussion about that odd behavior here, with some making accusations based on their biases. In my research, I found a questionable but possible answer to the one-night stay at the hotel. His wife is supposedly pregnant, and they had just come in from out of town. As for the scooter, according to locals, the cost of hotel parking is very high in that area. So, to save money, he threw their car down in the free garage and scootered back to the hotel.

>>>>>Edit: That was weird. Two of the times were oddly changed from what I had originally published. I hope that doesn't happen again. Thank you for finding it, @Jedidad.

Addendum: Just to clarify the purpose of this exercise...this timeline is intended to help provide a general sequence of events against which to check failure theories. This building didn't fail in some random sequence. The spreadsheet simply organizes survivor descriptions that have come from reasonably credible sources. How the survivors have been quoted is generally good enough for this purpose. This will help engineers and attorneys prepare to interview them.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Why did he want his scooter? He's just going to have to go back to the condo to retrieve the car the next morning to check out of the hotel. Surely he wasn't planning on hauling his wife and luggage back on the scooter.

Playing devil's advocate, I would say that his car probably has some kind of comprehensive coverage, which the scooter doesn't. But that would only apply if something nefarious was going on... which I am NOT implying.

I know I've done some illogical things when I was tired, so I'd be chalking it up to that.

That said, I'd really like to know more about WHY his electric was out. Not living in a third world country, having no electric at the breaker box, assuming my bill was paid up, would have me talking to a lot of people (electric company, security, condo employee) late at night... I'd consider no electric to be something of an emergency. It just seems really odd that unit 508 (IIRC) would suffer an outage hour ahead of the collapse when the lights were on in the rest of the building until seconds before.

BKNJ

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Why unit 508 might have lost power:

With all those AC compressors stacked on the roof, I will assume that each unit supplies its own power to its own compressors, up there.

If the guys working on the roof managed to wang (sophisticated electrical terminology) 508's compressor bad enough, there could've been a short. NORMALLY, that will trip the breaker for the compressor. But it doesn't have be that way. It COULD have tripped the unit's main breaker instead.

And then 508 would have no power.

spsalso

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Maybe all the intensive hammer drilling that so shook the entire building all the way down to the foundation also wiggled a few of the light bulbs loose and they really had power after all. It only seemed like they didn’t.

That’s probably the best explanation.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (BKNJ (Computer))

Playing devil's advocate, I would say that his car probably has some kind of comprehensive coverage, which the scooter doesn't.

No doubt police consider every angle, if only to find someone to blame it on. Well they have a purpose to fulfill. And, I've seen how NIS really operates. But since you mention this, you might also consider that his Tesla Oscillator could also have tripped the circuit breaker while he was fine tuning it and he had to find another place to plug it in. Ok, one of these two theories is crazy, but somehow they fit together. Telsa claimed he could knock down a mid rise with his oscillator btw or worse. I apologize for this post.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

3

#### Quote (warrenslo)

There are multiple reports of the initial collapse beginning at the roof:
111 said noises came from roof first
611 said cracking came from ceiling downwards
711 ring camera appears failure from above first in doorway area
904 said noises came from roof and they fell floor by floor to the 3rd floor
Finally, those two blue flashes of light in the x10 stack on the security camera footage to me look like electrical, as if something is falling through the x10 stack cutting the electrical wires from inside (maybe the HVAC unit?)
Repeating things don’t add to their validity. Particularly when you have to contort them to fit your perspective.

111 said nothing about the roof.

611 saw cracking in the seconds before the building collapsed. This was several minutes after all of the ground level failures had occurred. The building was mortally wounded at that point. And the loads were desperately trying to any path they could to take them. The cracks tell us nothing more than that the building was dying; and quickly.

Same for 711. You’re pointing at Richard Petty barrel rolling down the backstretch and shouting “Look at that dent in the fender there!!!”

904 said noises came from the roof. AS THE WHOLE BUILDING COLLAPSED AROUND THEM! Did they say they heard the roof collapsed several minutes before the rest of the building but decided to just wait and see what was going to happen? I missed that part.

Now we have AC units cutting through the middle of the stack as the building collapses? How does that even fit with your previous theory that things falling off the failed roof caused the ground slab to fail several minutes before the whole thing came down?

I’ll be honest. When you first started posting this stuff I thought you were just doing it to have one over on us. For whatever reason, I don’t know. Then you posted that PowerPoint and I realized it was much deeper than that.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (spsalso (Electrical))

If the guys working on the roof managed to wang (sophisticated electrical terminology) 508's compressor bad enough, there could've been a short. NORMALLY, that will trip the breaker for the compressor. But it doesn't have be that way. It COULD have tripped the unit's main breaker instead.

I'm trying to give the residents of 508 the benefit of the doubt that they checked the main breaker... and that they don't need an electrician to reset a breaker... but, granted, I may be giving them too much credit.

I look at it this way... if the electric stops at my breaker, it's my problem, otherwise it someone else's and they better get it back on ASAP or have a damn good reason it's off (and I have to get a hotel). Again, assuming the bill was paid. OTOH, the A/C is my problem... and I'll admit that if I was in Florida in summer and the A/C broke (well, beyond my ability to fix it), I'd be booking an air conditioned hotel real quick.

BKNJ

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

There were some conflicting theories on whether this was a planter box or not, potato cam but clear enough to verify it is not the planter.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98 (Computer))

whether this was a planter box or not

Just above and right of the left arrow? Yes that is where a planter was in plans and photos. It has moved away from the wall a bit.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@spsalso got me thinking:

I'm more inclined to believe the power was out than Eric Zion was making this all up for insurance or whatever. The primary reason was that Eric & wife were renting. Additionally, it seems other Zions had rented the place and seemed to be on good terms with the landlord, a FL attorney. It's possible an intermediary did the unit management and failed to pay the bills. I'd simply ask the electric company who was on the account and whether it was shut off.

Other than the electricity being out, Eric Zion's actions were unsuspicious to me. It's how I would react in June in FL. If you returned from your trip to find your AC, fridge, and phone chargers all out at 10:30pm and the landlord is a family friend, what would you do?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (Optical98 (Computer)28 Jul 21 00:13)

LOL, this pic tripped me up for a second --
Shivered your timbers, did it. OK, we need a new column for weighty things on the roof...
Let's see, a boat?

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Regarding punching shear pool deck takes out first floor theory, why didn't the eastern shear wall hold? We see that columns north of the western shear wall fell, but it still stood. That eastern shear wall ended up all the way over by the western one. Strange physics...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (Demented (Industrial)28 Jul 21 01:14)

wonder why folks who seem to be against FMEA enter the forensic engineering area.
...couple o' things
I think it's Federal Emergency Management Agency?
I think it's the National Institute of Standards and Technology that is doing, (and has been doing for some time,) forensic engineering

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Murph_9000 Came across this picture the other day and thought might solve the door question. Hopefully it uploads.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98 (Computer))

why didn't the eastern shear wall hold
It held one sense. It was still together pretty much and recognizable. I'm guessing the difference is the east slice that fell last was too thin to resist. Everyone was afraid the other one was going to fall while they were in rescue mode. And fall in the planes they were not designed to resist.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

SF Charlie,

Wouldn't say I shivered, I was zooming in on roof line pics that I've saved n clipped, trying to find one with decent pixels to help
Markbob find his section 2 door (I think I did see one with it hanging by a thread)... so flipping thru zoomed in... the boat really
stood out n gave me a WTH moment ^.^

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

253RWD

Nice find!

Jeez, looks like someone from 87th Terrace was sleuthing a bit.

Now show us the crane.....

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (BKNJ (Computer)28 Jul 21 04:13)

I'm trying to give the residents of 508 the benefit of the doubt
I have a wife. She's not even pregnant, but if something's going to cause her discomfort and she presents a solution, I'm damn well going to take her suggestion even if I think there might be a more simple solution, if my solution takes more than 37 seconds... Specially after midnight...

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (253RWD (Aerospace))

thought might solve the door question.

Yeah that's really coming to the rescue. Ask and you shall receive. But now we are going to have to hear about those loose a/c condensers sitting on the deck. It's seems they do not also sit on mounting racks with code approved systems. Or maybe I am seeing things.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Optical98 & Zebrasko: Re the planter. I think the planter box is on the plan and is still there, clinging to a stub of uncollapsed pool deck slab, now partly buried in rubble.
plan:

rotate 90 degrees to get:
image

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

AusG

"I think the planter box is on the plan and is still there, clinging to a stub of uncollapsed pool deck slab"

Except now it's half way up the height of the door?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (AusG (Petroleum))

I think the planter box is on the plan and is still there

Thank you for providing the plan. There were some photos later in the recovery that had some of that debris cleared and the planter box was a little more obvious. Does that mean this area was examined? I thought maybe the question was whether that was viewable in the tic toc image. That would have to be a "no". The angle would not allow that. I mean the claim that the "sky" or above ground level could be seen through the garage entrance - whether or not sky was meant literally? Language can cause confusion.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Looks like it's on the same level to me, but I'm not sure why this a big deal. If a box the same shape and color as a planter is about where a planter should be on the plan, and the slab it should be on is clearly still intact just there, why is this a problem?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

No, I'm thinking that piece fell down from the 12th floor, that triangle that is torn out?

Zeb, I'm with you regarding those that could pick out the planter and pool furn from beyond the gate...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98 (Computer))

Except now it's half way up the height of the door?

I had a thought about that when looking at the photo you provided. Now I can't recall what it was. Wait I will look again. OK. I think it's on the slab and not rubble. I mean I had to look at it a few times. The actual door is to the right and what that panel behind it is I don't know. Maybe it's access to the plumbing for the planter watering.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Couldn't that black arm looking part be something that helped brace that parapet up top?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98 (Computer))

No, I'm thinking that piece fell down from the 12th floor, that triangle that is torn out?

So say that's a piece of a balcony. Yeah that's the kind of question that does not have a very good answer. After that question is how did the debris get piled against it if it did not fall early? Good luck with that. I mean if that's where you are going. Someone will know what it is though.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Optical98: The large piece, your white arrow? Sure, good idea. I had no view on that piece at all. Zebrasko: yeah, there seems to be odd colored patches on the wall. IDK what any of them should be. The door is the dark... door-shaped thing... to the right.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Looks too thick to be a floor or balcony slab. I'm thinking it's part of the eastern sheer wall with the 13th floor being thinner just the way it is on the west. That would imply the 2nd portion of the collapse - the north side - also ripped part of the east wall just as the 1st portion ripped part of the west.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Auri (Bioengineer))

part of the eastern sheer wall with the 13th floor being thinner just the way it is on the west.

The debris piled against it is curious. Even if it was the triangle from the west stairwell above the 12 roof it probably got closer to 9.8 m/s/s than debris that followed the main section roof. Free fall vs ...what? Nothing remarkable there.

The thing that the triangle is resting against is actually more interesting. It's a very thick non-orthogonal piece of concrete at an odd angle to the structure. It has a beveled edge and it is not deformed or broken from what I can see. The end of it is clean and straight. This is the best close up photo of this area that I have seen and I have been looking for one. That's gotta weigh as much as two or three large planters if it is concrete. It seems next to nothing fell on top of it. ?? Of course it could be an optical illusion like many things. But it seems substantial enough that it took a bite out of the shear wall and was none the worse for wear. The apparent stains on the side do not detract from the impression that I have of a jersey barrier. Can't help it that's what I see. Now I'm not saying a Jersey barrier fell out of the sky. And it does not make sense. It's probably obvious and I'm not seeing it right. I will admit that.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Auri, me and the wife were staying at a hotel, and the power went out during the night to just our room. Management were having a big party on the roof and decided to turn off random rooms where the air con was running.

It was pitch black and by morning the room was a modest 35 degrees. (Vietnam). We never considered leaving the room or trying to contact anyone. Who cares? Power is out. Who the hell abandons a condo with windows just because the power is out? Makes little sense to me. But maybe i am just a tight ass.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (@SFCharlie)

...couple o' things
I think it's Federal Emergency Management Agency?
I think it's the National Institute of Standards and Technology that is doing, (and has been doing for some time,) forensic engineering
Failure Mode and Effects Analysis.
FMEA.

Sorry. I spent a lot of time looking for stress cracks in fasteners and weldments that initiated failure events in the past.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Just an idea because I have not a thought as to what that debris would be.

I don't think this is the right location for this to just fall down. If these stairs were fastened the way they should have been, there'd have been some, not a lot, but some, upper support on that roofing slab. If slab tor away at wall and around base, load on stairs and column would massively increase, with a rotational force clockwise.

Probably more likely more deck that sheared and tilted, possibly on a column. This again was an area of extensive concrete repair in the 90's. One of the sections that possibly only had either 305 stainless rods roughed and inserted, or 3 #5's. Hard to tell from the napkin sketch on the permit.

Edit: Yeah, it's just crappy ring camera video, but I really do suggest everyone listening to the video again for at least 30 minutes in a dark room.
Edit 2: Has anyone found or seen the staircase in the debris? Should be at the top of the pile yeah?

t=sqrt(2d/g)

Edit 3: Yeah, I don't know... Earlier large photo had a different angle.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Regarding scooter / car / hotel.

Perhaps it's as simple as they had to pay for parking at the hotel and didn't want to? Simple solution would be to park at home, return on the scooter, and keep the scooter in the hotel room. Next day return home on the scooter, get the car and go back to the hotel to pick up the wife / luggage.

If the hotel was close to home, and the parking charge excessive, I'd certainly be weighing up the pros/cons of this. Granted I'd probably decide my time was worth more than the money saved, but that comes down to personal circumstances.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Depending on where they would have gone for a hotel room on a Wednesday/Thursday in the late PM/Early AM hours, a vehicle break-in is more likely than that issue over expensive parking. There's also the possibility of the night clerk either not knowing how to or being unable to produce a parking pass, and parking between hours of 10PM and 5AM is prohibited in certain places along the beaches and Miami area.

Precision guess work based on information provided by those of questionable knowledge

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

All good points as well. Just playing devils advocate that there are plenty of rational decision points which might make someone decide that the car / scooter arrangement made sense.

Plenty of people seem to be happy to point out that it seems weird, without knowing anything at all about the people themselves or what they may have been thinking.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented)

Better yet, one has to wonder why folks who seem to be against FMEA enter the forensic engineering area.

fo·ren·sic
/fəˈrenzik,fəˈrensik

relating to or denoting the application of scientific methods and techniques to the investigation of crime.
"forensic evidence"
relating to courts of law.

noun
plural noun: forensics; noun: forensic

scientific tests or techniques used in connection with the detection of crime.

Scientific methods should follow the evidence. This building seemed to fall from the bottom up, not the top down.
Should we focus our search for answers on the roof? Nothing dropped from the work being done on the roof should have lead to a partial collapse of this building. There is a very good reason why people like the "Building Integrity guy" haven't mentioned OSHA anchors nor tar kettles. They are irrelevant as far as the failure of this building and have only been discussed to further some misguided theory.

We see many signs of poor maintenance and design deficiencies as well as issues with concrete quality and plan adherence with regard to rebar placement. Perhaps these are areas where we should place our focus and stick to scientific methods instead of the wild conjecture and conspiracy theories that has been seen here.

I find it insulting to think anyone here is "against FMEA".

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented (Industrial))

Earlier large photo had a different angle.

Ah yes. You have shown the triangular tear-out is attached to......column and the wall is the portion I was calling "stained" contiguous with tearout past the column and is planted down in the debris pile. Or the debris is planted around it. Can't tell anything from a single perspective. I knew I was wrong about what it looked like. Nothing to see there. But then you can't tell when that fell in the sequence either. I mean not really. Nothing piled on top of it but that doesn't mean too much because its on the edge of the pile. is there a reaction between it and the slab or did it fall into a hole?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (MaudeSTL)

As for the scooter, according to locals, the cost of hotel parking is very high in that area. So, to save money, he threw their car down in the free garage and scootered back to the hotel.

Ah, that makes sense, thanks. He'd then zip back to the condo in the morning to retrieve their car to bring the wife and luggage home.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented)

I still have my doubts about this causing the tearout we see though, but work was likely done drilling in that exact location. Would they have used the same 3/4" anchors?

The columns with the tear outs appear to be the ones that had the concrete beams that held the larger A/C unit. When the original collapse happened these beams pulled out from the top of the columns leaving the shape seen in the demolition video. It seems the lack of rebar at this point may have prevented those beams from pulling down those columns and helped stop the collapse at that point.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented (Industrial))

Edit 2: Has anyone found or seen the staircase in the debris? Should be at the top of the pile yeah?

There are at least a few sections of the NE staircase visible.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented)

Edit 2: Has anyone found or seen the staircase in the debris? Should be at the top of the pile yeah?

Wasn't sure if you meant the northeast stairs as sgw1009 delineated above, or the exterior stair to the machine room? If I'm not mistaken, I believe these are the latter.

That photo was from July 2, but I believe they hadn't removed much from the area due to the proximity of the remaining tower. While I was searching for an older photo, I found one from June 24 at a different angle which I believe shows the same stairs (red arrows). Forgive me if this particular point has been addressed previously, but I do recall mention of tie-downs with the roof work and AC units. I hadn't noticed what appears to be a yellow ratchet strap tied off to one of those red AC platform beams, said beam kinked at that point. The other end appears to be attached to one of the new roof anchors, possibly? That kind of deformation, to me, shows the anchor put up a pretty good fight as the building tore apart, and it eventually popped out of where it was attached. (To be clear, I'm in the "accumulated pile of exacerbating factors leading to eventual failure" camp. I just found this interesting as there's been so much discussion of this area of the roof.)

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

253RWD, thank you for the photo showing the door to the middle roof above. Fortunately, I had agreed earlier with Santosi81 and Murph_9000 that a door was there.

Now, if you look closely at the photo you may see something interesting that you, Murph_9000, and Demented (who also posted the same photo above), may have missed. In the photo underneath the stairs you can see three air conditioning units that are not tied down to foot-high metal supports like they should be. And they appear in a place where air conditioners are not shown on the architect's drawings. Clearly, these air conditioners are either old ones being replaced or new ones to be installed. If unsecured air conditioners can be found on this part of the roof, then it is likely that others also can be found on the penthouse roof adjacent to this area, from where one or more of them could have fallen down to the deck below.

Question. Do you know when this photo was taken?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (arbitraria)

I hadn't noticed what appears to be a yellow ratchet strap tied off to one of those red AC platform beams, said beam kinked at that point. The other end appears to be attached to one of the new roof anchors, possibly?

I'm not too sure a ratchet strap would be strong enough to kink that beam but a lifting sling would be. I can't find a spot on the still standing portion of the building where the other end may have been attached so it could have been attached somewhere on the part that collapsed.

Edit: It also looks like the beam twisted nearly 90 degrees if that helps anyone.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Nukeman948 (Electrical))

I can't find a spot on the still standing portion of the building where the other end may have been attached so it could have been attached somewhere on the part that collapsed.

Looking at the roof view from 2021 (with the new unit on it), the eastern (right) two beams are painted red, while the two beams under the HVAC unit are not visible. So the crimpled beam would have to be the eastern-most beam of that assembly. This is away from the standing portion and towards the portion of the building that collapsed. Looking at the roof view from 2021, the crimping would have occurred on the right-most (east-most) beam, about 1/3 of the way up from the bottom (from south to north). This is essentially the center of the roof, so no obvious need for an anchor point at that location. No ideas on what that was about.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (sgw1009)

Looking at the roof view from 2021 (with the new unit on it), the eastern (right) two beams are painted red, while the two beams under the HVAC unit are not visible. So the crimpled beam would have to be the eastern-most beam of that assembly. This is away from the standing portion and towards the portion of the building that collapsed. Looking at the roof view from 2021, the crimping would have occurred on the right-most (east-most) beam, about 1/3 of the way up from the bottom (from south to north). This is essentially the center of the roof, so no obvious need for an anchor point at that location. No ideas on what that was about.

I agree with all of that. Among the things we don't know is why was the sling there? Did the red iron fall first and rip out the anchor, or did the point it was attached fall first and pull down the red iron? It almost looks like the iron was bent upwards but it my have bent when it hit the debris pile.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Arguments against the roof being a trigger.

One of those AC units weighs 200lbs, there's a parapet wall, and the roof has almost no slope. An AC is not just going to fall off the roof cause it's not tied down and there's vibration or 20mph winds. You'd have to put the thing on wheels and take away the wall to make this scenario plausible.

If the roof did collapse first, everyone who saw it is dead and nobody reported it to 911.

So the theory is relying on some mystery force, or a sneaky roof collapse that killed everyone who saw it like The Ring.

I'm not ruling it out entirely, just saying the odds are very slim.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

So one would think that the larger beam would be under the four smaller beams, giving them support. But looking at the photo below, it shows that the opposite is true: the larger beam is on top of the four smaller beams. So this means that we are seeing the bottom view of the assembly (colors of which are unknown), with the crimped beam still being farthest from the standing section of building. Note that this is the old HVAC unit, and the new unit was installed to its right. But the support assembly is the same.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (sgw1009)

So whatever was tied to the beam was to the west of the HVAC assembly, not the east.

And if we're not confused enough already, did the strap go to the east, or maybe under the unit to the west? Were they using it as fixed point to test the new roof anchors? Maybe it went over the unit to hold it down because they were changing the method of securing it to the steel? Good questions often lead us to more questions.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Reverse_Bias (Electrical)28 Jul 21 16:52 Arguments against the roof being a trigger. One of those AC units weighs 200lbs, there's a parapet wall, and the roof has almost no slope. An AC is not just going to fall off the roof cause it's not tied down and there's vibration or 20mph winds. You'd have to put the thing on wheels and take away the wall to make this scenario plausible. If the roof did collapse first, everyone who saw it is dead and nobody reported it to 911. So the theory is relying on some mystery force, or a sneaky roof collapse that killed everyone who saw it like The Ring. I'm not ruling it out entirely, just saying the odds are very slim.)

Agreed that it seems very unlikely that the AC units were at all involved in initiating the collapse, but there is some confusion when people talk about the “roof first” theory. The AC units aren’t the only thing that could have fallen off of the roof. The original plans show the roof parapet to be CMU block with Reinf. Concrete columns at 20 ft supported on the roof slab which is cantilevered beyond the building. This system has a number of weaknesses so one can imagine several plausible scenarios where a 10 ft long section of this parapet wall could have fallen off the roof and crashed through the plaza deck. In fact you could probably argue that this is more likely to have occurred than a spontaneous collapse of the plaza even granting that the plaza was poorly designed and maintained. The question of why the building collapsed instead of a more localized failure I think will come down to a plethora of errors in the original design.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (tmwaits1)

This system has a number of weaknesses so one can imagine several plausible scenarios where a 10 ft long section of this parapet wall could have fallen off the roof and crashed through the plaza deck. In fact you could probably argue that this is more likely to have occurred than a spontaneous collapse of the plaza even granting that the plaza was poorly designed and maintained.
This one can’t imagine a plausible scenario where the roof just falls off. Has anyone put one forth even?

But say we do have a spontaneous collapse of the roof where a whole ten foot (wide? long? square?) section just falls off the building. How is that more likely to have occurred than the plaza failure?

The nature of the abnormal punching failures in the plaza slab indicates something was severely amiss there. Doesn’t it? That’s all in plain view. No imagination necessary.

That roof section that just fell of(weighing how many tons???) would have hit the ground below at around 70 mph. It would not have sounded like knocking noises, or construction, or even a “wall collapse.” Or any noises from above for that matter. It would have sounded like a bomb going off outside. And would have looked the same to anyone peering out the windows after they heard it.

It would not be a disturbance that you stroll casually over to security to say, “Do you hear the sound? It doesn't make sense in the middle of the night, early morning, people doing construction.”.

People on the ground floor next to where that would have fallen would not have reported it as being something that could be ignored:

#### Quote:

Nir described the noises as sounding like “construction knocks” and was disturbed that they were being made at such a late hour, with her son and daughter fast asleep in nearby rooms.

“I thought someone had decided to renovate their apartment in the middle of the night,” she said. “At first, I ignored it. But a few minutes later I became upset about it and left the apartment.”

Show me what the failure looks like. I want to see the where and how this big ol’ chunk of roof departs the building. If there’s a plausible scenario for that, sketch it up for me. Let’s figure out what the mass and impact of that would have been when it hit the ground.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

There was an earlier discussion regarding which government entity was in control of the site. Apparently Miami-Dade is.

In the video, it's clear that Miami-Dade is preventing Surfside from starting their own investigation.

So Miami-Dade declared the site a crime scene. Maybe all disaster sites are classified a crime scene when there's no apparent reason for the disaster. Maybe there is EVIDENCE of a crime. Maybe it's a cover-up attempt (I highly doubt this one). What other reasons would Miami-Dade prevent one of the preeminent experts on building collapse ( Allyn Kilsheimer ) from examining the site?

https://miami.cbslocal.com/2021/07/27/surfside-full-forensic-investigation-condo-collapse-site/

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Spartan5

I was thinking about that 'knocking sound' she mentioned as well. What about pipes? Sometimes pipes can make knocking sounds. Did they start that Generator perhaps? Maybe more units were without power than the one mentioned.

Did the building have propane or gas hook-ups? There was a Kitchen off from the Rec room, did it have a gas stove?

Just some thoughts...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Spartan5 (Civil/Environmental))

Show me what the failure looks like. I want to see the where and how this big ol’ chunk of roof departs the building. If there’s a plausible scenario for that, sketch it up for me. Let’s figure out what the mass and impact of that would have been when it hit the ground.

Let's suppose that whatever was done on the roof causes a portion of the slab to fail over the x11 stack. There is some shear puncture at the outside columns and the slab hinges down somewhat... maybe 20 or 30 degrees. Nobody is in PH-A at that hour to see it, but now a couple lose pieces (~15lbs) of the parapet or large crumbs of the slab where it broke fall and either hit the balcony immediately below of ricochet down and hit the pool deck, making "construction noises" that reverberate through the building. At some point, a large section of parapet (>15 feet) lets go, takes out the balcony railing below and falls 12 stories to the pool deck starting its failure.

That's kinda what I see as a remote-remote possibility. I'd love to hear how this couldn't ever-ever happen.

I'm not a member of "team roof" or any of the more outlandish conspiracy theories, including AC units, cars crashing or boats on the roof. I suspect the authorities have evidence that negates these possibilities because if it existed, something would have leaked to the media by now.

BKNJ

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

I was thinking about that 'knocking sound' she mentioned as well. What about pipes? Sometimes pipes can make knocking sounds. Did they start that Generator perhaps? Maybe more units were without power than the one mentioned.

Did the building have propane or gas hook-ups? There was a Kitchen off from the Rec room, did it have a gas stove?

The generator only supplied emergency power for one elevator, fire alarms and fire pump, security, water supply and emergency lighting for locations like the stairwells, lobby and exit paths. No sump pumps except for the elevator shaft seem to be in the original plans neither from normal power nor emergency power. Hmmm...

The building was designed to have all electric HVAC, water heating, cooking appliances and laundry equipment and didn't need gas. (still may have had gas but I have not seen any evidence or need for it)

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

6
Like Spartan5, I'd like to see some quantitative basis from the "roof-first" crowd.

How do we go from a rebar potentially nicked by a hammer-drill to Marvel Universe level destruction, and how do you get the timeline to actually make sense? Was it because, as one poster suggested, the crew was actually doing work under the cover of darkness to skirt permitting and inspection mandates being enforced during the day? If so, did they base jump to safety as the penthouse and roof collapsed from beneath their feet?

Was it the pallet of rolls of tar paper (are we creatively counting up to 120 rolls yet, or are we still at 49)? If it's the pallet loading, what about the live loading on all of the PH/roof slab area that surrounded the localized area covered by a pallet? Was it zero, and if so, how does that cumulative effect compare to the design roof live load applied across the entire roof surface and the internal forces that would result?

And one of my favorite angles so far: the poster who keeps invoking some sort of Morabito collusion, where the structural Morabito guy was in cahoots with a Morabito concrete repair/restoration guy.

Help me to understand the roof-first theory through analysis, as opposed to sensationalized story-telling and rampant conjecture.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Thank you Nukeman!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)
I'm in the middle of a project. I downloaded the earliest copy of the CCTV file from YouTube. I'm copying the frames one by one. I'm having to register each frame, because whoever captured the security screen, was moving their (smartphone, camera, whatever) around as they captured it. In just the first 20 frames, I have been astonished at what I see. As many have agreed, a large portion of the roof is missing in the earliest frame that is legible (if you can apply that word to a picture). The next and most startling thing I see, is that the collapse does not happen as a single fall, but in stages. I'll attach the draft PowerPoint. If you would like the individual frames, I can provide that as well...

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@Seppe - I think the Morabito collusion angle is conjecture based upon the concrete restoration company staff including one Phil Morabito; both companies having Florida & Maryland locations; I recall seeing somewhere that they've worked together before on similar projects but I could very well be mistaken. I know papa Morabito brought them on board to fulfill the concrete restoration portion of the project, in a seemingly familiar relationship (I'll go see if I can find a quote momentarily}.

It wouldn't be the first time various firms have handshake agreements to throw each other work, roll projects together to "make things easier" for the client. Some are fairly legitimate, others not so much. Judging by the somewhat-less-than-inspiring plans we've seen from them, the shadier persuasion is definitely within the realm of possibility. I don't see it as a conspiracy-level theory as much as questioning potentially dubious or even corrupt business practices.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (I think will come down to a plethora of errors in the original design.)

I second that. We know any successful creation is not just an assembly of successful ideas. It must include the proper application of those singularly successful ideas and the vision to know when another good idea should be added.
Then it needs someone to step back a bit and look to see if the entire project as designed is even a good idea.
Forcing something to work is just not a good idea. Hoping that it will is even worse. I am not suggesting this building was designed on hope, just that there were parts missing that could have prevented the sudden and total (for the section not demo'd) collapse.
Please excuse the comment - it does not advance the quest for details in this case, but it could possibly benefit someone down the line.
Thanks,

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

First, a question. According to preceding posts,it's not unknown for snowbirds to 'rent' their empty units to contractors who live in and renovate the unit during the off season. Is there any suggestion that any of this 'stealth' work was going on in the building? Might unauthorized work in a neighboring unit have caused the power outage in 508?

Could the PH parapet have been damaged by workers hauling materials for the roof construction over it, or by accidentally tapping it with a suspended crane load, etc? Not to the point of the entire parapet falling, but enough to crack some chunks of concrete, possibly even days earlier? Water seeps in, vibration from further work and perhaps even the elevator, and a few chunks fall. Say in the 50 to 100 pound range. It appears that anything falling from that area could have fallen into the planter below. If so, landing in the dirt and greenery could have muted the sound. Would the abrupt impact of 100-200 pounds of falling cement be enough to collapse the deck in that area if the deck was already overloaded and weakened?

I tend to believe that the failure was a result of a combination of questionable design, shoddy work (both initial and repair), corner cutting and work on the beach and building next door which may have further compromised the structure. But, I am open to the possibility that there may have been a straw that broke the camel's back on that particular night.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@Zebraso
Yup, nothing to see here.

@Nukeman948
As scary as that is, I do agree that this failed repair prevented further collapse.

@Arbitraria
That be the one, thanks. I was too focused on the beams that I missed the latter.
I brought up the anchor cable before, as it was called in the permit. Been trying to find more details on it because I suspected it was attached to the side of E2, which would mnore explain the tearout on that column we see. I do believe it was anchored somehow and it did put up a fight as it fell.

A ratchet strap however there raises some curious custions.
Even a bad building inspector would likely take issue with that. Why would this have not been noticed, said to be fixed, etc?
Secondly, could this ratchet strap have been used to tie off to a roof anchor and the cooling tower to perform the load test of a new anchor?
I'm trying to disprove roof first and this is one of the key areas that I feel would have needed to collapse to initiate the roof first toppling that we see with the dibris distribution that was present from day 1.

I'm mostly concerned with the weight of the new retrofit A/C on a modified steel temporary structure with a known to be poor full beam replacement, that had all sorts of weird shit done to avoid stressing the slab it was on, but every measure to not shore loads was taken here. On a water soaked roof too, with lesser quality concrete, and all that other work that was going on around and on it at the time. I feel the middle of the upper floors and sections of roof failed first at this location. It is possible that this was a result of the initial collapse, not the initiator. Don't get fooled, just have an open mind. There are many distinct and different collapses that happened over 10 minutes or so, possibly an entire day. It didn't just go down because a column went missing at the base. We know concrete gives us signs it's in trouble. Those signs are just hidden under latex lipstick that was slapped on this pig.

Edit: Oh, a ratchet strap, especially a 3" or 4" wide one most crews who transport heavy things have, can and will bend steel beams like that before they themselves yield. Done it plenty of times. Ratchet strapping something into place because of warped material when pie heating is not allowed. You'll cave steel in if you go a little too far.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (SFCharlie)

The next and most startling thing I see, is that the collapse does not happen as a single fall, but in stages.

Starts at the lower x11 stack, then the UPH hinges along the E-W interior at or just before the corridor showing the PH (12th floor) soffits proud to the camera, PH-11 balcony gives way and swings vertically to the east, striking the lower x12 units, where the columns supporting the massive eastern lobby level beam group fail, and so on.

A lot of motion not only in this area and direction, but towards and away from the camera as well.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

The biggest problem for the 'roof first' theory (at least the variant of it that has something drop off the roof to start the plaza failure) for me remains the fact that no-one, especially 111, reported anything falling from the roof. If it had bounced off all the balconies on the way down then 611 would have noticed that. We know the plaza failed before the main building, and we know it failed somewhere in front of 111, if not first then certainly early on (from the TikTok video).

There are certainly lots of reasons to be suspicious of the roof work. It's even possible that the roof slab failed (we know it was water saturated in areas, particularly around the area that collapsed) and maybe even that the penthouse roof crushed the whole penthouse with nobody noticing, if it was empty. And it does seem too much of a coincidence. But I don't see a mechanism for that to result in plaza slab failure, which I think we all agree happened before the building column failure.

@SFCharlie, thanks for fetching the freeze frames. I am now somewhat more convinced that by the time of building collapse, the 13th floor is missing in the collapsed section. I've taken a grab of frame 3 from your set, where you can clearly (well, by the standards of the video) see the floor correlation, along with the Bing aerial shot for comparison.

You can clearly see the strip of paired non-balcony windows running up to the 12th floor balcony, and the 12th and 13th floor balcony parapets. But the 13th floor itself is missing (at least the front portion) in the collapse area. We don't know if that happened 5 seconds earlier or an hour earlier though. (Someone posted a few threads back that the alarm should go off if sprinkler lines are cut, but I think everything is serviced via the corridor, so if the slab is hinging and only the front part is dropped, they might well not be cut.)

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (arbitraria)

I think the Morabito collusion angle is conjecture based upon the concrete restoration company staff including one Phil Morabito; both companies having Florida & Maryland locations; I recall seeing somewhere that they've worked together before on similar projects but I could very well be mistaken.

MC was working out of CP&R's Florida address back in 2018. That doesn't prove any particular nefarious actions, per se, but the two companies are clearly closely associated.

http://web.archive.org/web/20181105052724/http://m...

They worked together on Dolphin Towers in 2015, getting an award for it:

#### Quote:

Morabito Consultants, Inc. was an Outstanding Award Winner for Dolphin Towers Condominium – Remediation project in the 2015 NCSEA Annual Excellence in Structural Engineering Awards program (Category – Forensics/Renovation/Retrofit/Rehabilitation Structures under \$20M).
https://www.structuremag.org/?p=10101 (article written by Frank Morabito, so it's a self advertorial, but has useful / interesting information).

A benign explanation for the relationship is that MC simply borrowed / rented some office space from CPR after a successful project, to expand their activity into Florida. And Phil Morabito may have just discovered a job opportunity due to the relationship. It doesn't have to be nefarious, and there's no specific evidence of wrongdoing. Companies do have a habit of continuing to work together after a successful project, which is all we can really say with much certainty.

I'm giving them the benefit of the doubt, in the absence of evidence.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Red Corona)

You can clearly see the strip of paired non-balcony windows running up to the 12th floor balcony, and the 12th and 13th floor balcony parapets. But the 13th floor itself is missing (at least the front portion) in the collapse area.

I interpret that first frame of video as being after the central south facade has dropped roughly 1 story. Of the 5 lights in that section, I see the living rooms of 1010, 1011, 1210, and 1211; with the lit pair of non-balcony windows being the 1111 bedrooms. I also see the master bedrooms of the x12 stack hinged downwards to match the drop of the x11 living rooms. The lights are still on briefly because everything is basically just hinged down at that point, so the cabling has not yet been ripped apart.

For me, the PH floor and roof is there, not sure about the PH and roof parapet over the x11 units, and it's the basement or first floor that is missing at that point.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Caulk?
Who thought caulk crack repair on a slab was a good idea?

This would have been hidden from view and covered with pavers. Man was that parking deck full that night.

Also wonder where that .5" depth actually landed.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

> with the lit pair of non-balcony windows being the 1111 bedrooms

I think it's quite clear that there isn't a parapet directly above that lit pair, and there is an unlit pair above? So that must be 1011 (lit) and 1111 (unlit) because there is a parapet going across above the unlit pair and not directly above the lit pair.

It's also actually an interesting question as to why we can't see the balconies on the collapse section. They are quite clear on the S part (that never collapses) and upper floors of E part, and you can clearly see the (what I'm saying is) 11-12 and 12-13 full width ones. Is it just because it's moving so the video artifacts obscure them?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Red Corona)

I think it's quite clear that there isn't a parapet directly above that lit pair, and there is an unlit pair above? So that must be 1011 (lit) and 1111 (unlit) because there is a parapet going across above the unlit pair and not directly above the lit pair.

1211 did not have a parapet, it had a full width balcony with railing. I think the balcony slab is there directly above the lit pair. To me, the continuous vertical line in the facade, between the x11 bedrooms, is interrupted directly above the lit pair, by the 1211 balcony.

The upper PH balcony has a parapet over the x11 stack.

Edit: Yes, I think the movement is blurring all of the x10 and x11 balconies. x12 has essentially not moved much at that point (on the east end, the master bedrooms on the west end of x12 are probably moving)

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (Murph 9000 (Computer)28 Jul 21 23:48)

I think the movement is blurring all of the x10 and x11 balconies
The thing that's bizarre to me is that there is NO movement for frames 0 - 5

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (SFCharlie)

The thing that's bizarre to me is that there is NO movement for frames 0 - 5

A possible artifact of a cheap or badly coded motion activated camera system? An artifact of playback starting, throwing up a static image until the playback fully kicks in? That's total guesswork, but the simplest explanations I can think of.

Things have already moved at the start of that video, whether it's just the top or the entire central southern facade. I don't think there can be any doubt that the tower has roughly 1 story missing from that area, we just have different opinions about exactly what is missing / moving at that point.

Also, look at the bedrooms (west side of the units) of 412, 512, 612, 712 (or just the bedrooms from the low level blur up to the obvious 912 balcony). The facade appears quite deformed, as you'd expect from the adjacent x11 living rooms dropping.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Red Corona)

The biggest problem for the 'roof first' theory (at least the variant of it that has something drop off the roof to start the plaza failure) for me remains the fact that no-one, especially 111, reported anything falling from the roof. If it had bounced off all the balconies on the way down then 611 would have noticed that. We know the plaza failed before the main building, and we know it failed somewhere in front of 111, if not first then certainly early on (from the TikTok video).

Maybe not if something fell from the western end of the parapet. There were only two balconies below, the rest of the floors were double windows. The floors that did have balconies in that location, tennants were either absent or did not survive, so there's no way of knowing what they saw or heard. The 'construction' sounds 111 heard could have been small chunks falling, and the 'collapsing wall' could have been a larger piece which caused the failure of the deck.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Sorry to digress … is there an app for this site? If not, will some one provide a link to the instructions on how to reply directly to someone’s post? 🙄 Sorry, it’s one of those days. BTW - this is a terrific site. Thanks!!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

From frames 15 to 17 it also didn't seem to move. To me. the camera was injecting very short pauses into the video. I've seen POE network security cameras do this when viewing the live stream from the camera so the pauses are just not worth any further hand wringing to try and figure out.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (Red Corona (Computer)28 Jul 21 23:33)

why we can't see the balconies
I'm trying to corollate what I see in the video with the real building, so I took a couple of snaps in Google Earth Street View

and

I think it is difficult to see the balconies edge on...

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Yea, I think the "pauses" in that frame by frame series are likely not real pauses, but something due to the sampling rate of either of the cameras. Some in the series are likely the same image.

Really grasping at straws with the endless analyzing of very poor video. I know better vid must be out there, but man they are keeping this investigation TIGHT. No leaks that I know about.

I still think I see a red-ish dust cloud early in the collapse vid, which could have come from the patio collapse. Visible down low, partially obscured.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (253RWD (Aerospace)29 Jul 21 01:34)

instructions on how to reply directly to someone’s post

No app that I know of
Copy the name date and time line from the post you wish to reply to
In the Reply To This Thread box at the bottom of the page, click on the cartoon w/speech bubble
Paste the name date and time line in the query box that pops up, click OK
Write your reply, preview it to make sure you said what you meant. you may need to page down.
When you like what you wrote, click submit

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (MechinNC (Mechanical)29 Jul 21 01:59)

Really grasping at straws with the endless analyzing of very poor video.
Yes My intuition was to say it was imposable. But I felt I need to present evidence in the midst of all the bickering. However some times I see lights turning on and off with no downward movement. or I see leaves on the tree in the foreground move in the wind, so no, it is not duplicate frames, but real stops and starts...

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

SF- Good work, thanks.

I'm still not convinced that some images are not copies of the prior ones. Especially towards the last several frame, once the collapse really gets moving. It's just not rational that the collapse would pause at that velocity.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

It's a video of a screen playing back surveillance footage, taken on a phone or some other camera. Most surveillance cameras will have a 24 or 29.97Hz frame rate, with the latter being common in the US. Most screens have a 60Hz refresh rate. Most phone cameras will be at 30FPS. Having all three frame rates sync up perfectly would take a miracle. So there will be some duplicate or mis-timed frames in any such video.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (MechinNC (Mechanical)29 Jul 21 02:41)

I'm still not convinced that some images are not copies of the prior ones.
Neither am I, but I do see a light come on in frame 9, with no apparent movement, so I don't know...

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (Eufalconimorph (Computer)29 Jul 21 03:32)

So there will be some duplicate or mis-timed frames in any such video.
Yes! ...bound to be...

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

It's highly likely that the video of the collapse didn't start (at least the one we've all been seeing) until after the collapse began. You can be sure that the camera and NVR system where this recording took place is in the possession of investigators for further analysis.

There is likely video from the camera system at CTS and assuming that the NVR survived - it's in the hands of investigators and nothing's been released yet.

You can also be sure that investigators canvassed every building with a line-of-sight to CTS and is in possession of those videos - and done so as soon as possible after the collapse so they wouldn't lose the recordings due to overwriting of older footage.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

5
SFCharlie - that's good work, but I don't see it proving anything.

I think the lights are messing with the camera image quality. Also, in low light cameras tend to blur motion so that could be messing up the image quality as well.

To me, that column without lower level balconies is ending with the 11th floor balcony right above the windows with lights on. Then, there is the strip that is the 11th floor, another strip that is the balcony/parapet at the 12 floor and then the roof parapet. A possible reason the top level parapets aren't as wide as they should appear is because the facade wall is dropping first so the floors has hinged down enough the camera is seeing them from an angle instead of straight on.

To me. all the collapsing floors have already dropped about a floor.

I see nothing that definitely points to part of the roof missing or falling off first. I don't see how any more details can be gleamed from that video based on how crappy that area appears.

I can't make out anything at the left of the collapsing area because of the lights.

I actually saw most of the above just looking at the Youtube video. Scanning these frames just confirmed what I already believed.

I really don't see enough of a difference between these groups of frames to be able to claim the building stopped dropping during these frame groups. From the crappy footage, I would be more inclined to believe it is the camera or the playback device causing these pauses.
08-11
12-15
17-19
20-22
24-27 - It collapsed upwards slightly if you believe these are true frames of the building.
29-32
33-34

Of course, I'm sure others will give long written explanations on how the frames must be different.

There is a reason why the established structural folks on this site have mostly given up on this thread. It's because they don't speculate and chase wild theories and other unrelated crap, not because they can't due to their profession but rather because they know how stupid it is to do so.

I haven't seen very much for postings that would be considered FMEA in the last few threads. FMEA would involve looking at a failure mode and then examining what the result of that failure would be. For example, if a transfer beam failed what could happen. It's not posting on about labor skill or who did what renovations or chasing a white car even though there isn't an ounce of evidence it was involved in any way.

Finally, this isn't a forensic engineering area, it's an area to discuss engineering failures. But, if you want to talk forensic engineering, then there's not much of that going on with the stupid throw the spaghetti at the wall and see what sticks that's happening here. It all happened in the first few threads when the little evidence that was available was first examined and discussed as to it's meaning. This is when the established structural folks mostly stopped posting because they know it's impossible to do any deeper forensic examinations without more evidence and the evidence had dried up. They also know how pointless it is to try and convince the "what if" wild theory crowd that it's pointless to keep at it. Remember the "it was a car hitting a column, end of story case closed" post? Dealing with that level of stupidity drives rational folks away.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (SFCharlie)

However some times I see lights turning on and off with no downward movement.

Most of the “lights” in the x10/11 stacks are reflections from glass that is no longer in place. The two bright flashes from the X10 stack are reflections from a fire alarm signal on the exterior landings of stairwell 1. There are a couple of exceptions but it’s a very macabre subject I don’t feel is appropriate to discuss in detail.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Would you really want to watch a high res video of the collapse footage? I mean you'll be watching people die. I think there is at least one person caught on footage in the low quality version.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Thank you SFCharlie. Mammoth effort.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

SF Charlie,

Regarding the "established structural folks" having given up on this thread bit, nah they're still here with their sock accts....obviously.

This looks to be the most successful thread on this site, and it will probably continue to be until we get real answers and closure to this shocking event.

As more evidence becomes available we'll all be here to analyze and discuss it.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

16

#### Quote (Optical98)

This looks to be the most successful thread on this site, and it will probably continue to be until we get real answers and closure to this shocking event.

How you measure successful threads is not by the quantity of replies, but by reply quality.

In the 20+ years I have been an active member on Eng-Tips, the majority of this thread (and its recent related parts) does not qualify as quality, and in my opinion, takes this forum site to the dark side of conspiracy-theory trash.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Seems there's very two distinct groups here. Those who believe the collapse happened over a day or so, and those who believe it happened instantly with no other outside factors possible.

@Seppe
There seems to be multiple roof first theories. Some of which I don't agree with as things like A/C units falling off the roof, punching into the pool deck, and still being recognizable.

I've been doing my best to try and find any and all modifications to this building, and map them out on which columns, slabs, and beams have been worked throughout the start of the building's history. It all centers around a certain arrangement of columns, E-K2(or 2.1 depending on which version you look at) and E-K4, and then a lot of work on the slabs between the H to L column lines south of row 9, as full depth repairs to balcony slabs did extend into interiors of units. A large portion of this work was done by the same engineering firm and same contractor, that seems as though they were using outsourced staffing firm day laborers to keep costs down as much as possible, and even in the words of the field inspector/supervisor, passed incorrect repairs anyway.
Anyone that's been into enough homes/units and demoed them knows very well what a cracked slab looks like when you view it from the top, without ever needing to see the slab. Tiles don't just magically crack in the same row for no reason. This, along with slanted door openings along slab supported by columns I8-L8, with signs just starting to show near M8. M8 being the very suspect place over a "how in the fuck did this get built?" design error if I am not mistaken. Seriously, I'm still scratching my head because the 1-17-80 change of column type revisions include that elevation change that I don't see mentioned anywhere in the construction or revision notes. These plans should have been reviewed and kicked back with a lot of angry red pen scribbles. It doesn't take a rocket surgeon to realize there wasn't much supporting the generator room; hell, even Morabito knew that which is why they were going to put a larger steel support beam in there to redistribute the load a bit better. This work being done already or not is still questionable. I haven't seen permits showing it, but at this point permits don't seem to matter for anything other than proving poor engineering, planning, and construction.

TL;DR, I'm concerned with work over the poor roof structure as well as additional weight having lead to an upper slab failure. Not falling far, but our good friend F=MA helps us there. Especially with the loss of an upper beam between E and H, the one the cooling tower was being supported by, along with what it appears to be a portion of CMU wall for the PH corridor that needed external bracing on the opposite side, if this section were to collapse first, say only 2-3 floors down (We have to take into account the recounted story of the family from unit 904. They got very lucky in their survival, but their account does show that the collapse did have a pause in it between the upper floors falling and the lower floors falling. The upper floors outside the main hallway above units xx0 (I believe) and xx5 fell first and stopped at the 8th). This initial falling of or through the roof could have even been stopped by the cooling tower tether.
At this point, I am very uncertain of how the load redistribution would react, and what I am trying to figure out with all of the new information about repairs, weight, etc that I have found), but I believe this would have easily caused a massive shock force at the base of one or more columns somewhere at the lobby or garage deck level. Garage deck seems to be the place as indicated by the TikTok video. From then on out, the main collapse with the deck bringing down the building, and what we see in the security video potato cam, commences. The loss of the internal structure along those columns/rows, in my fully out there mind, could very easily explain the "void" the building collapsed into in the center, as if it imploded right in it's foot print, as well as the delay between the S and N sides of the building collapsing, as it's very clear the S section fell first at the main corridor line, followed by the N side of the building collapsing at that same line.
Extra waster weight on the pool deck is still a contributing factor as the rain over the days would have stressed that deck even more, and not helped the situation any.

To me, this makes total sense with what we see and does not seem all that farfetched. Yeah I have some crazy ramblings at times, but who doesn't have stupid ideas that need to get shot in the foot? We know these contractors deviated from the set rules. To me that's like throwing a bunch of color on a black and white painting. We can't just judge the painting for it's black and white work.

Before coming to this structural area of South FL, I came from a world where a .003" error missed in inspection can cause catastrophic unscheduled disassembly and loss of life. Things don't just blow up for no reason. Failures and multiple events typically lead up to the ultimate final incident. I don't care if ya'll think I'm crazy (Hey, his name is Demented, he must be insane!) or a conspiracy theorist. If I would have been allowed, I'd have been down there day 1 looking at the ends of rebar with a portable SEM. Sometimes there's blurred lines in tensile and shearing failures, and both can work hand in hand together. At least metal likes to hold it's final shape for us to see it's exact failure mode down to almost near the atomic level if you really really want to get crazy with it.

I'm still very curious to see the condition of these piles and if they are poured or precast. Yet another thing that hell, what could normally be moot of an additional 1mm of drop over years, could have been enough to put further stresses on very shallow rebar that was supporting the weight of cracked slabs that were only being held up via the rebar.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

9
LionelHutz and Ingenuity's posts directly above are a good summation of my thoughts.

I've been practicing structural engineering for my entire career, and I've visited this website for at least the past ten years (only lurking, at first). The structural engineering community on Eng-Tips, from my perspective, is a really good group and a fantastic resource. Their absence from the latter threads of this topic is telling.

As ashamed as I am to admit this, I check in on this particular topic perhaps once or twice a day still, with a sort of "trainwreck / can't look away" type of mindset as it relates to the posting itself. At this stage, quite frankly, the discussion is equal parts useless and flat-out embarrassing. The champions of the roof-first theory (you know who you are), for example, defend their own incessant back and forth as if it is some form of "no stone left unturned" analysis that others on here are just too closed-minded or shallow to consider. Guys... in reality, all you are doing is sensationalist babbling that, structurally speaking, is the easiest to dismiss. You so badly want to be right that you've blinded yourselves to the spirit of the original discussion. You just can't seem to abide any explanation of building failure that is a boring, highly plausible one, so you heap your efforts into tangential theories to create/maintain a buzz.

I'm sorry for even posting again, as it probably just sustains a topic that should have wrapped up at least five threads ago.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I'll again repeat a joke an old MSE prof told the class. This man was a well known SE/ME in the South FL area too.

A group of engineers took a taxi together to a convention. As they were driving through some farm land, the taxi driver says "Hey, look at that cow with one eye!"
All of the engineers covered an eye with one hand, turned, and said "where?"

I'm sorry if I've soiled your Structural Engineering thread. I didn't know this was strictly SE. >.>

Edit: BTW, I'm pretty sure finding the location of that upper roof and the stairs completely shoots down the theory of the upper wall tilting forward allowing unsecured A/C units to fall forward. So, you're welcome.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Without the NIST report ( due in a few years) or the footage from the installed surveilance cameras around the pool, it is not likely that we can be assured of the root cause of the instant failure. However, all of the above discussion points can point to a direction for upgrading future inpsection procedures and regulatory statutes.

It was reported that some insurance companies are already pulling out of the market for insuring buildings designed prior to the year 2000 upgrade of Florida building regulations . That could lead to a lot of older condos being uninsured, so the units would need to be purchased for cash without bank loans. That suggests a step change in value for the older units is forthcoming. Another evolutionary approach might be to duplicate the de facto process in Hawaii, where the condos have a fixed ( 50 yr ?) life related to their initial land lease life, so a known end of life is prescribed in the purchase agreement.

Not yet discussed above is the interesting theory that the garage floor slab was not directly supported off the pier caps, and that allowed a reservoir of salt water to accumulate under the slab and attack the support piers in a manner that cannot be examined without removing portions of the floor slab . I guess we will just have to wait for the NIST report, hopefully not compiled using political science.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Pretty much the only thing this thread is now demonstrating is that the Dunning-Kruger effect is alive and well.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@ Mocrowizard, LOL!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Demented

I was looking at a few photos of the roof area, there does look to be some measures were being taken to "try" and help the stability of the corridor wall, ie...it was unstable.

What is the point of the rope or cable tying off that walkway, in section 2 there is that odd brace looks as if it's helping hold up that wall and the last image, the area doesn't look squared and you can see the deep moisture lined areas from the upper corridor wall. That wall is directly connected to the PH that complained to her son about the creaking and groans waking her up at night.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I'm just going to say that I have not offered up even one conspiracy theory.

I have offered evidence of contributing factors to the overall failure, my first post was regarding the weakness of the generator room slab. My further interests have been that there is evidence of a fire or some sort of combustion on the north side of the building...where there just happen to be many combustible factors.

I've not put forth a formal hypothesis because I can't say what happened first, the collapse or a fire, but I will continue to peruse and gather info as I find it.

I also sometimes come across items that may help others in their perusals, and enjoy the bits of humor we find along the way.

Grown professionals can conversate without calling others "Trash" and "Stupid". If you have nothing to add to this thread other than badgering or name calling, you should be embarrassed.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Theories and speculation have been called stupid, not members. Who should be embarrassed exactly, the ones posting theories with absolutely nothing to back them up or the ones calling those theories out?

As an example, the amount a building would have to shift to make a door 1" out over 3' is a lot. I can't envision any way the one side of the frame dropped that much while the other side remained in place without there being major wall damage to fix. I'd be much more inclined to chalk that up to poor construction with the rough wall opening not being constructed square causing the door to be installed crooked.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

LionelHutz

I don't recall a theory on door alignments, perhaps that was just an observation?
Sometimes several of us have come across a picture, a permit, differing plans and conversed over what was followed thru on or not... those are not theories.

But I have found usually when I ask questions....as in there were plans to install a natural gas line...did it happen etc. I get very good feedback.

You went on about my mention of a white car or 2... if you go back to where that all started, I've never been on the vehicle vs column team, not bashing them... I just happened across a picture that looked very much like a wheel inside a column.

Demented quickly corrected my vision, and several of us saw the humor in it, but there are still some question as to what happened to that particular car, it was involved with the NW portion of the collapse, in so far as it was dented and the airbags inflated. Possibly from falling pipes, we don't know and there was NO THEORY put forth..

But no one can outright claim one way or another that their theory or hypothesis is the absolute truth atm.

I feel like with the number of sock accts at play, I can't be sure who I'm conversing with anymore - this is my only acct. And I feel like some are trying to turn this into a 4chan monkey show with propping up their own opinions and then demeaning others.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

An observation. One where nitpicking over slight, and I mean slight, trapezoidal shape was noticed. Less than 4mm at most. I have no idea how that grew to an inch.

Precision guess work based on information provided by those of questionable knowledge

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

in so far as it was dented and the airbags inflated. Possibly from falling pipes, we don't know and there was NO THEORY put forth..

Curtain Airbags (not to be confused with side thorax airbags), will deploy if there is deformation of the roof structure without regard to the operational status or vehicle occupancy.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Wow. Sounds a bit supercilious to disqualify any comment by any person not listed as a structural engineer. It seems to be conveniently forgotten that the catastrophe occurred primarily due to a substandard design provided by a structural engineer, was inadequately inspected and analyzed by a structural engineer, and that the implications of a collapse of a residential building designed and inspected by a licensed structural engineer threatens every member of the public, including those that are not licensed to practice structural engineering in the state of Florida. It would seem that it is too soon to discount any possible failure pathway , and the theories submitted by structural engineers are no more or less possible than those of other observers at this point in time, aside from those that are physically impossible.Methinks thou dost protest too much.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

> @LionelHutz To me, that column without lower level balconies is ending with the 11th floor balcony right above the windows with lights on

That just goes to show that different people will see what they think they already know, when presented with unclear imagery. To me, frame 3 (the one I posted in my comparison pic), and also 18, clearly show the strip of separated windows below the 12th floor balcony going up one floor above the lights. Frame 0 (although full of artifacts) and 1 also appear to show something where floor 13 should be, at the right hand half of the collapse area.

The 13th floor should be present over the double pillar, and the right side, but not over the left side (there was no floor 13 there). I'm struggling to see in your version what the visible structure on the left side on that floor is.

I also put the (not under dispute afaik) floors on the right side in so we can see how much the building has dropped. In my interpretation the camera has actually triggered pretty much at the start, the floors still align well, only floor 13 is missing, and it looks like (with the eye of faith at least) you can see that collapse in frames 0-2.

> @Santos81 Most of the “lights” in the x10/11 stacks are reflections from glass that is no longer in place. The two bright flashes from the X10 stack are reflections from a fire alarm signal on the exterior landings of stairwell 1. There are a couple of exceptions but it’s a very macabre subject I don’t feel is appropriate to discuss in detail.

We're looking up from ground level, what are those windows reflecting? Surely we'd be looking at the sky reflected? The 'lights' in 911, 1011 and 1111 look like real lights. But yes, if they're real lights that means people turned them on and didn't get out in time - nicer not to think about that. I don't think it's particularly relevant to the engineering 'what happened' side.

Do you know what floors those fire alarm signals were on? That would clear up which floor is which.

@Demented/@Optical - there is definitely bad news involved in that roof/PH floor.

Here is my attempt to make a plausible 'roof first' story. But I'm still not convinced - it just seems a huge coincidence that two separate bits of the structure would be in a bad way at the same time.

- The day before, roofing contractors get up there and cause some roof level overloading (bad roof anchor drilling sites hitting some rebar, or putting heavy stuff on the roof of 13, or something)
- The penthouse roof slab starts to puncture with the roof columns at K/L/M 9.1. It doesn't collapse, because it's still supported by the walls, which aren't structural but they're still well built enough to take a single slab load. This causes the 'creaking' (slab top rebar ductilely failing in tension around the puncture? load redistribution noises) heard be 1211 the previous night. Nobody notices because the deflection is small and the slab is hidden under roofing material
- Failure continues and the next night the walls and roof columns fail. Initial stages cause 'construction noises' (as per 111) as load changes in the structure. The PH roof crushes floor 13's facade (spraying glass from the balcony windows and dust down in front of 111) and falls down onto floor 12's roof.
- Some or all of the roof parapet falls onto the planters in front of 111, this could be the 'loud crash like a wall falling'
- This extra load causes the pool deck to fail and we know the story from there

Alternatively, the failure causes a redistribution of load which affects M9.1 and causes the M9.1-M11.1 beam to detach from M9.1. This then puts the plaza slab into overstress and starts the plaza failure, without anything falling. In this version the failure of the PH roof 'sounds like a wall falling' (because it is), and that noise is transmitted through the columns so is loud in 111. This also wakes up 611 but she was asleep so didn't register it consciously.

I still favour a plaza-first failure, but if you think that frames 0-2 of the collapse show floor 13 collapsing first, perhaps a partial failure of M9.1 from the loss of support from the pool deck is what causes the roof slab to let go.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Since you asked, I looked again and yes from the start all along I have actually believed the lights are on the 11th floor which puts the 12 floor balcony above the lights and the the double rows of parapet above that. I'd get the floor numbers right if I would stop counting the roof parapet as the balcony for the 13th floor.

I don't agree with the angles on your right side floor lines.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Red Corona)

We're looking up from ground level, what are those windows reflecting? Surely we'd be looking at the sky reflected? The 'lights' in 911, 1011 and 1111 look like real lights. But yes, if they're real lights that means people turned them on and didn't get out in time - nicer not to think about that. I don't think it's particularly relevant to the engineering 'what happened' side.

Do you know what floors those fire alarm signals were on? That would clear up which floor is which.

They’re reflecting the ground lighting. The exterior luminaries are not the only part required to be sea turtle compliant; the glazing is as well to minimize interior light transmission. The only interior lights that are visible in the footage are at locations where the balcony doors are either open or the glazing units have detached from the envelope or shattered before power was lost. Several balconies were occupied. People seem to be omitting material displacement when analyzing the footage.

The flash heads are on the north elevation of the floor landings at every floor. I believe the artifact I circled in red is from one.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (LionelHutz (Electrical)29 Jul 21 03:49)

that's good work, but I don't see it proving anything.
Right, All I think it proves, is that I was right several threads back, to say that a video from a smartphone, whatever, of a security system display, that's out of focus, (and compressed in the phone and again in YouTube) is practically immune to analysis.

SF Charlie
Eng-Tips.com Forum Policies

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

As a reminder, closest-to-original public source of the video is at:

Fullscreen, pause, scrub. I'm seeing too many transcoding artifacts like blurriness and repeated frames on Youtube or other Twitter sources.

#### Quote (Santos81 (Specifier/Regulator))

The two bright flashes from the X10 stack are reflections from a fire alarm signal on the exterior landings of stairwell 1.
I don't think that can be. Those flashes illuminate a bit of the left side of building, and they last way too long. Were the light sources from the opening next to the western stairwell, they'd illuminate a good chunk of the mid section building instead. They'd perhaps be synchronous unlike in the video, and much shorter than electric sparks. A typical xenon flash is 5 microseconds. (One can be seen on exposed 13th floor passageway - two strobes, a few seconds, another two strobes, each strobe occupying exactly 2 frames.) A typical arc/induction spark is ~10 milliseconds and the were 12 tubes going east from each meter room. A single exposure at 30 fps naturally maxes at 33ms.

Edit: I see the fixtures on every floor in the surviving open area next to stairwell. I'm just not sure they flashed at all. Maybe they're unusually dim for how recessed they are, or you'd expect almost uniform illumination bouncing off building or smoke.

Also some of those window lights were not reflections... too square, and reflections move as the building tilts. The flecks seen in 1112 and then 912 could very well be reflections. The lights that vanish at the same time as 1209, not so much.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (4LionelHutz (Electrical)29 Jul 21 03:49)

24-27 - It collapsed upwards slightly if you believe these are true frames of the building.
This is why each frame must be registered The smartphone, whatever was moving around quite a bit.

SF Charlie
Eng-Tips.com Forum Policies

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (Auri (Bioengineer)29 Jul 21 19:44)

As a reminder, closest-to-original public source of the video is at:

SF Charlie
Eng-Tips.com Forum Policies

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Auri)

They'd perhaps be synchronous unlike in the video, and much shorter than electric sparks. A typical xenon flash is 5 microseconds. (One can be seen on exposed 13th floor passageway - two strobes, a few seconds, another two strobes, each strobe occupying exactly 2 frames.) A typical arc/induction spark is ~10 milliseconds and the were 12 tubes going east from each meter room. A single exposure at 30 fps naturally maxes at 33ms.

The strobe heads are located both interior and exterior at every non ground level exit. One of the interior fixtures in the UPH corridor is visible momentarily before disappearing. The units flash at a rate of 1FPS for 4 cycles, pause for 5 seconds, then repeat with asynchronous flashing alternating between each floor. Now add in more asynchronous flashing from circuit delay along with the different frame rates it was played back on the front desk display, the device used to record the playback, which was then uploaded for distribution, and viewed at every display frame rate, it’s going to look strange.

Look back and note I did not state that there are ONLY reflections. A small number of interior lights are visible and an even smaller number of exterior light sources of other origin are visible on some balconies.

The Surveillance system at 87 Park captured the entire event from multiple locations at 60fps/4K. It has continuous recording but will not play back at that quality at the Lobby console nor without action event queue markers.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Any ideas on how long it might take NIST to finish their report? Do they ever release any kind of preliminary report before a final one?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

When I play the video I see some flashes that look, to this electricians eye, like arc flashes, a couple that look like the lights were on in that condo unit, even one that looks like a cell phone light for just a second in the last section to fall. I can't see that any of these lights prove anything one way or another. But there were a whole lot of flashes that could line up perfectly with the full moon that was out that night reflecting off the window panes as they fall. That just makes it that much harder to attribute the flashes on such poor quality video to anything meaningful.

Que the tidal forces wingnut theories...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@Red Corona
"Alternatively, the failure causes a redistribution of load which affects M9.1 and causes the M9.1-M11.1 beam to detach from M9.1. This then puts the plaza slab into overstress and starts the plaza failure, without anything falling."

I believe this is what happened rather than debris falling to the deck. There doesn't seem to be any evidence of it really. If the roof collapsed anywhere, that slab centered under E2.1, H2.1, E4, and H4 is likely the most suspect place with the work cenetered around it to avoid shoring.

Anyway, I forgot who mentioned it, perhaps Santos81, but they posed a good question.
Why is a building with a 35 year life-limit being allowed to continue occupied in such condition, with such bandaid work done? How do we get regulations or anything changed to stop stuff like this from happening? The white hard hats with the clipboards don't seem to care. I witnessed a roof slab being poured in the rain yesterday.
I do my damndest to blow the whistle on job sites and in shobs when it comes to work like this, however shutup and do as your told.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Santos81)

The Surveillance system at 87 Park captured the entire event from multiple locations at 60fps/4K. It has continuous recording but will not play back at that quality at the Lobby console nor without action event queue markers.

You know this for sure?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Missing/disorganized building records at a commercial storage facility rented to former Surfside inspector... the plot thickens
https://archive.ph/kdVy7

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Auri, is it related to this?

They released this a few days ago, alone. I thought that was odd.

Not implicating McGuinness, but odd email to release.
Edit: to release on it's own as the email file, not a PDF.

FOIA request issues makes sense now.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Ohh yesss...the trickling of bread crumbs...I did mention this would happen ^^

Thank you Auri!

When I was tracking the Units and their Occupants, I found that
Maricela P Prieto was listed as the owner of Unit 1111,
she was not the occupant, Gloria Machado was and sadly passed in the collapse.

These are public records. I wonder if Maricela is any relation to Ross?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98 (Computer))

I wonder if Maricela is any relation to Ross?
Probably not; Prieto is a common Spanish surname. The owner of the adjacent unit 1112 is better known, though. Annette Goldstein, former board member ca. 2019, daughter of builder Nathan Goldlist ... Nathan Reiber and the Goldlists met up in Canada.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented (Industrial) 29 Jul 21 23:08)

Odd. None of the photos work anymore.

Probably deleted because property is listed as being off the market. It's interesting that the unit was for sale.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

https://www.miamiherald.com/news/local/community/m...

"Working with the Rapid Response Research Facility of the National Science Foundation’s Natural Hazards Engineering Research Infrastructure Program, NIST has installed accelerometers to measure building vibrations and a seismometer to measure ground vibrations at the 12-story Champlain Towers North condominium, which is a near twin of the south tower. The data will be used to validate computer modeling of Champlain Towers South, says NIST, not to evaluate the condition of the north tower."

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Images…

Well done. Nearly 100% accurate.

#### Quote (Demented)

I believe this is what happened rather than debris falling to the deck. There doesn't seem to be any evidence of it really. If the roof collapsed anywhere, that slab centered under E2.1, H2.1, E4, and H4 is likely the most suspect place with the work cenetered around it to avoid shoring.

The cooling tower and support assemblies didn’t begin to move until after the 2nd collapse portion fell. If you look at the Surveillance video frame by frame, it’s path and sequence is completely visible. It ultimately falls to its final position just before the 3rd section falls and the dust cloud obscures the view.

When the skin is peeled away, things look a bit different and remove the roof first theories from the list of suspects.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I can't see anything clear enough in the video frame by frame.
I also fail to see how removing the skin removes that theory entirely. Help me understand. If tower didn't fall, sweet. Let's check that one off as a nope.

If the slab below the support structure fails, but the tower remains is still a possibility. This questionable work in that area involves some questionable work to avoid shoring the slabs for 3 floors. We shores floors to support them to prevent collapse, yes? Lets say we come up with a gimmicky way to remove a beam for a full beam replacement. What we're gunna do is carry up sections of beam, and then bolt them together. Tap into one of the A/C units and run a little transformer welder to stick some shit on. It's bolted, doesn't need to penetrate 100%. We'll weld some small sections of beam to the sides of it next to the support, drill some holes and bolt this thing right on down to the column. Now we weld this beam to the cooling tower. Job done, awesome.

Now, balcony repair company comes along and removes the beam, but uh-oh, this weird bolted together weldment with some only 8 3/4" by 5" Hilti bolts that bolts it down to the columns sags.

They didn't call in a crane to lift it.
They didn't shore 3 floors down to support jacking the beam and tower back up.
This work also got done rush rush and given the stamp of approval even though the field inspector/SI was not witness to the pouring or completion, but somehow the steel beam was back up supported under a concrete beam with minimal cure time. Something weird went on.

Edit: But then again, this was the same crew that shored the x11 and x12 stacks straight down to on top of the pool deck. Smart crew this one was. Multiple days reported they didn't even have work plans or shoring plans on site.
Why can a SE design something and a company be allowed to go around the SE's design/plans and hire a new PE to quickly sketch up a "let not have to go into people's unit's" shortcut? Craziness. It's almost like this was done on purpose to hide it from the SI, who was one of the engineers of the original consulting form overseeing the concrete restoration work.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented )

I can't see anything clear enough in the video frame by frame.

#### Quote (Demented )

I also fail to see how removing the skin removes that theory entirely. Help me understand

I’ll put together a 3D PDF, with some FEA model examples. But to be brief, the available alternative load paths based on the framing layout and debris field doesn’t jive with a top down modus of failure.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (Jedidad (Computer)29 Jul 21 20:15)

Any ideas on how long it might take .... Do they ever release any kind of preliminary report
It has been claimed that like NTSB, NIST will take a year or two for the full report, but also like NTSB, they will release a preliminary report in less that a couple of months, that will only contain matters of fact, but no analysis. (They claim)

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Debirlfan)

The 'construction' sounds 111 heard could have been small chunks falling, and the 'collapsing wall' could have been a larger piece which caused the failure of the deck.

Both are unlikely to have occurred in the garage as none of the people who used it from 11:00 to 1:15 have reported driving over small or large chunks of concrete.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Demented)

Tap into one of the A/C units and run a little transformer welder to stick some shit on. It's bolted, doesn't need to penetrate 100%.

You don't seem to have much respect for other peoples work. Why is that?

There was 400 amps @ 208v 3 phase power available at that location that could have easily fed a bank of 50 tig welding machines.
You have no proof of your claims. Give it a rest.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

2
How about we bifurcate this? Part A can be facts as they become available, maybe a handful of posts a week for months to come. All the noise in Part B can then be ignored by 98.75% of us.

I’ll see your silver lining and raise you two black clouds. - Protection Operations

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)
DISASTER & FAILURE STUDIES
Update on NIST’s Investigation of the Champlain Towers South Collapse

#### Quote (Remote Sensing of the Site)

Cameras and lidar used by NIST and its partners scan and record the site of the Champlain Towers South condominium.
Drones carrying cameras are being flown over the site to help with the geotagging of evidence and to capture changes at the site.

#### Quote (Evidence Tagging and Preservation)

NIST will be deploying an electronic evidence tagging system that uses RFID chips so that electronic records are associated with every piece of evidence collected.

#### Quote (What We Can Learn From Champlain Towers North)

NIST has installed accelerometers to measure building vibrations and a seismometer to measure ground vibrations at the Champlain Towers North condominium

#### Quote (Next Steps)

NIST is in the process of putting together the National Construction Safety Team that will lead the technical investigation.

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

"Building officials of Miami-Dade County suspect deferred maintenance rather than weak building codes or an inadequate 40-year recertification process..."

So those are the three choices.

Apparently those building officials never thought of:

incompetent design

incompetent execution

incompetent inspection

corruption

sleaziness

A person could wonder why.

spsalso

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

incompetent design, incompetent execution, incompetent inspection, corruption, sleaziness, extreme weather? Nope, none of that here!
--- oh, and I forgot, seawater flooding in the streets

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (SFCharlie)

It has been claimed that like NTSB, NIST will take a year or two for the full report, but also like NTSB, they will release a preliminary report in less that a couple of months, that will only contain matters of fact, but no analysis. (They claim)

Unlike NTSB, they have not had news conferences several times in the immediate aftermath. These usually feature the lead investigator making a presentation and answering reporters' questions.

spsalso

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (spsalso (Electrical)30 Jul 21 03:34)

These usually feature the lead investigator making a presentation and answering reporters' questions.
or the chairman of the board propounding on his stature and impotence I mean importance.

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Davefitz)

"Wow. Sounds a bit supercilious to disqualify any comment by any person not listed as a structural engineer."
I don't interpret the criticisms being put forth against some of the posts as saying only structural engineers should be able to comment. I am not a structural engineer but I am disappointed by many of the multiple posts by some who have taken photos from multilisting RE sites and pointed to 'deformations' and 'misalignments' and said look at the evidence of pending structural failure. RE multilisting photos are taken with wide-angle optics and digitally warped/stitched to look nice. One post asked about the ovoid witnesses on the concrete surface of a concrete sample and posited this looks like some type of boring and post-op concrete patching. Until called out this comment as intimating shoddy work and nefarious activities were afoot. Trying to use the grainy low-res security camera video as conclusive evidence to say 'look, the penthouse caused this' seems uninformed and at worst bordering on conspiracy mongering. I have checked out enough of this listing to see I have seen enough until NIST comes out with an official report. Everyone have fun and thanks!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (spinspecdrt (Materials)30 Jul 21 03:37)

Grassy Knoll
did that just teleport in from Texas?

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Something just occurred to me. The only people who escaped were in 111 and 611, directly above. They escaped because they ran (respectively) to the lobby and the stairs by the elevator.

I had always assumed that perhaps other people had attempted to escape, but had tried to use the other staircase, and been killed when it collapsed. However, the articles quoting the Israeli team state that virtually everyone was found where they were expected to be, which suggests they didn't attempt to flee.

So, were the residents of the -11 units the only ones who received any warning?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

4

#### Quote:

One post asked about the ovoid witnesses on the concrete surface of a concrete sample and posited this looks like some type of boring and post-op concrete patching.
I got a kick out of that one. My thought was that anyone who had not seen enough plywood to know what a standard patch looks like when knots are cut out, and who has never seen a pattern left on fresh concrete by wooden forms does not have enough real world exposure and has no business even guessing about structural matters.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

A modest proposal:

For all these buildings being (re)-inspected, allow only people from out-of-state, with NO business ties to Florida, to do the inspections.

Everyone in Florida should recuse themselves in this matter. We just don't want even the appearance of self-interest here. Right?

And I'm sure the building officials of Miami-Dade county would agree.

Locally, I think we could spare a couple of people for awhile, for the common good.

spsalso

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (Brian Malone (Industrial)30 Jul 21 03:40)

Trying to use the grainy low-res security camera video as conclusive evidence to say
I never intended the grainy low-res security camera video as conclusive evidence of anything. When I looked at it frame by frame, it was more worthless than I had imagined... Sorry!

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote ("Wow. Sounds a bit supercilious to disqualify any comment by any person not listed as a structural engineer.")

the issue might be somehow related to structural issues...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Debirlfan)

So, were the residents of the -11 units the only ones who received any warning?

I have been unable to find any indication that the surviving witnesses heard a warning on the side that collapsed. The Nirs (111) got lucky…they had activities that kept them up later than usual that night, and their apartment was right above the epicenter of the collapse. So they were able to hear and feel the building’s attempts to redistribute its load and get out of the building in time. Ileana Monteagudo (611j was awakened by the deck collapse, which she calls a “supernatural force.” When she saw symptoms of impending collapse and ran to the staircase, luck played an important part for her too: she chose the staircase that survived, instead of the closer staircase that didn’t.

After the building collapse, several people who were in the part of the building that remained standing said they heard the alarm after the building had collapsed.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (ENR)

Miami-Dade Building Officials Suspect Poor Maintenance In Surfside Collapse

Not surprising. If the building had major structural issues it would have failed a long time ago. People gotta remember - something like this isn't caused by a single event but a series of events in the days/hours/minutes leading up to the collapse, caused by prolonged deferred / neglected / poorly executed maintenance over a period of many years since the building was first constructed.

The building survived the initiating event (likely the pool deck collapse outside of unit 111) and remained standing for 7 to 15 minutes. That was plenty of time for evacuation which never happened (lack of emergency planning). The weakened concrete/rebar could only hold redistributed load for so long. If the same initiating event happened 40 years ago when the building was finished it would have likely survived.

Why did the building collapse? Because the pool deck failed. Why did the pool deck fail? Because of water infiltration into the structure. Why did water get in the structure? Because of failed waterproofing. Why did the waterproofing fail? Because it hadn't been maintained over the years. Why wasn't it maintained? Because the condo association likely didn't have the wherewithal to have the deck waterproofing inspected / replaced at regular intervals. Why did that happen? Because the condo association aren't subject matter experts in building maintenance and/or didn't feel the expenditure was necessary. Etc... etc...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

MaudSTL and Debirlfan

Unit 904, Mother and daughter of Gonzalez family. They heard something and ran out their front door into the hall, took 5 steps and 9th flr fell to 8th..
It's a tough article to read, they're both still in the hospital I believe.

I can link the article if you need.

https://www.nbcnews.com/news/us-news/mother-daught...

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98 (Computer))

Unit 904, Mother and daughter of Gonzalez family. They heard something and ran out their front door into the hall, took 5 steps and 9th flr fell to 8th..
It's a tough article to read, they're both still in the hospital I believe.

Ah, that's my point. 111 heard noises over a period, and had time to go back and forth to the lobby. As I recall, 611 had time to throw on clothes, gather a few items, and make it to the far stairs. Whereas 904 apparently only had seconds, and other tenants either heard nothing, or didn't have time to respond. To me, that suggests there was initial movement/sounds which were mostly contained to that column and not felt/heard in the rest of the building. Whether from above or below, it seems there must have been a gradual failure centered within the -11 column.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Noise doesn't always wake older people when the hearing aids are in the charger or on the end table.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (the catastrophe occurred primarily due to a substandard design provided by a structural engineer, was inadequately inspected and analyzed by a structural engineer, and that the implications of a collapse of a residential building designed and inspected by a licensed structural engineer)

Can't let that go without comment - mostly in jest, of course.
So why is it that if some A/C system fails miserably and some occupants get hot and a bit sweaty it does not immediately draw an 8 segment forum response with as many SEs chiming in as there are M and Es here?
Maybe the SEs work in a more risky and exciting profession? From a risk/reward view, it is not too smart, I will quickly agree.
But for the moment this SE discounts the influence of a failing 600 pound roof mounted condensing unit - no matter what head pressure it developed or voltage it operated at or even if the half horse cooling fan became unbalanced and vibrated the anchorage loose.
With that said, Dave, I would like to buy you a drink should we ever meet.
I do appreciate being warm in winter and cool in summer, thanks to Mechanical Engineers.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

@Nukeman
I have respect for others work, just no respect for shoddy work. Hard concept to grab, but there was a lot of "good enough" done on this building to be as cheap as possible. I used to joke a lot at work about stuff being good enough you could throw it off the roof and it'd survive. Yeah, you know what, a co-worker's rails actually fucking survived that fall. I gave him props.

Maybe I worked with these guys in the past.
If anyone in SoFla knows a loud mouth drunken POS drunk who wears penny loafers to job sites while screaming about tits and ass, you know this isn't the only cooling tower. The aluminum ones this dude did on that Target have glued on bolt heads.

The work on the W side, as well as the permitting and plans there, hell of a lot different than the ocean side. The town only seemed concerned with turtle lights on the beach side, but making the street side beautiful and correct.
Sorry, but even the welds were not done to the new engineers callouts. Clear as day in the photos from Morabito. So yeah, I'm gunna knock what would have been a fail if a CWI would have inspected the weldment. If we start allowing bullshit to slide, we're going to start seeing more issues with structures. When are people going to have the balls to stand up, put their fist down, and demand it be done right?

And yeah, you're right, you could power a bank of tig machines up there. These days inverter machines are so nice I can get 200A at my torch out of a 115v wall socket. You're not dragging a tig up there though for that job. There was also no crane, so that's a no on hoisting the Trailblazer. You're not dragging leads 12 stories up either and expexting to be able to weld. A small AC/DC 220v transformer power soure was carried up.
I got my first Dynasty 200DX around this time they came out. Aint no way I'm dragging that to a roof in the FL rain reason.
BTW, where in any of their plans for the beam replacement did it call for supporting the upper beam that was being supported by the steel beam, with a lower beam on top that was resting on the slab? I haven't found that in any drawing, permit, nothing so far.

There seems to be 2 crews that did a few jobs on this site, and did it very poorly. Even reading the entirety of the filed reports and inspections, the work was knowing done incorrect, but passed off by the FI, SI, and town building inspector. And this was concrete restoration work on the roof, columns, balcony, interior slabs, AND POOL DECK. Hell, even if the pool deck did fail first, and the building really did just crumble and fall, which is a possibility that I am fucking terrified of, so what if I'm chasing crazy, ignore it, focus on the very damning evidence of shoddy work that was done to the support structure of this building by these crews. Poor maintenance indeed, but not by the condo board as I've seen suggested by a few.
I'll keep chasing my tail in lala land until my FOIA on the images from the above mentioned work is handed over. Sadly at this point I think those pictures may be gone.

@Santos81
Blurrier than the TiKTok video, lol. Yeah I guess that's what it is. I suspect you've seen the full videos as I think you've hinted at in the past so no reason to doubt what you've seen. Scratching that off the list.

Have newer models begun to take into account the rebar replacement, or lack of, as well as delaminated sections of full or half depth slab replacements?
BTW you still got those flow surveys? Was interested in seeing that.

@Waross
Until then, I had never seen spots like that, and as you can recall, I highly suspected they were NOT patches. We don't see those patterns on the tops of slabs or the side of walls in pre-cast structure from the foundry's that have been involved, so sorry I've never seen them before. For the last 15 years or so all I've seen if OSB for wood forms. I do my best to avoid wood and have no shame in admitting I know not a damn thing about it. I even asked our wood shop guy, and he's never seen that, and he's been working with wood since before Jesus; round, oval, and the occasional square is all he's ever seen until I showed him that. Learn something new every day.

Also no, this was a varied age condo. The Avg age likely being somewhere in the 40's.

@Spalso,
To add to that, could we let out of state construction firms build everything too?
I've done 3 month stints at timeswith a certain Texas company who's been doing a lot of work in the below Orlando area for the last dozen or so years. It is a whole other world of proper that I just don't see with Florida based companies.

@Nessman
Planter drains were upgraded and waterproofing was replaced. Maintenance was done. Crews just neglected to do the job correctly as can be seen from the odd layering in places.

@MaudSTL
The FCP had a silence feature for certain alarms to be programmed in during certain hours. I need to read the manual for it again but I believe you could even program the system to only flash the fire lights but not trigger the buzzer even in the event a fire handle (jefferson alarm) were pulled. There's no indication that this was ever programmed to be silenced, but another possibility in the "why were there no alarms" until after.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Debirlfan)

So, were the residents of the -11 units the only ones who received any warning?

Adding to MaudSTL and Optical98's responses - I don't think they were there only ones, but it is possible that the sounds, sensations, and visual cues experienced in the x11 stack were the most alarming, and happened just early enough in the collapse that those handful of people had time for their flight instinct to kick in. (Obviously 111 had a good chunk of time they observed peculiar noises, but it wasn't until the collapse was visibly in progress and very apparent that the severity and panic prompted quick escape.)

We don't know if the woman in 410 heard or felt something that caused her to go out onto her balcony, or if she was already out there and through sheer coincidence happened to see the pool deck cave in. Same for the people on their balconies on the northern side of the building - were they just hanging out, or did they come out to investigate noises or sensations? Was it one unit's residents, or multiple units? I'm not sure if TikTok lady knows that answer, or which units they came out of, but she did try to convince those people she saw to evacuate.

I suspect that investigators have unreleased video from various sides/angles that shows exactly how many residents had some kind of advanced warning, and given the number of people who made it out vs. those who didn't, there was likely variation in how strong and/or easy to interpret those signs were. Add in the variables of disorientation in someone woken from sleep, and the number of units that were unoccupied at the time (thankfully there were many) and it's hard to be able to discern a pattern.

The part of me that still has some remaining un-jaded soul is haunted by the security camera video from 711, I can't begin to imagine how surreal and utterly horrifying it must have been to experience that first-hand.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

Unit 904, Mother and daughter of Gonzalez family. They heard something and ran out their front door into the hall, took 5 steps and 9th flr fell to 8th..

@Demented has mentioned this several times too. I’ll add the link to the spreadsheet over the weekend. Thanks.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (nessman (Computer))

remained standing for 7 to 15 minutes. That was plenty of time for evacuation which never happened (lack of emergency planning).
There was lack of emergency notice. We know the silent alarm was triggered by 1:16:39 am courtesy of the 911 alarm company call. The building didn't collapse until ~1:22:20 am. Usually those alarm systems progress to full alarm within 3 minutes. It's possible someone silenced it seeing as it was just a plaza collapse - and sadly they're innocent! It takes an engineer, or thoughtful physicist, or specific training to realize how much a ground level collapse threatens the tall building nearby.

This might happen again if we don't independently brace building boundaries next to collapsible space, or else train everyone to evacuate a building if something nearby sinks through. It might not be a degraded plaza next time ... could be a rogue truck, a battery fire, a terrorist...

#### Quote (spsalso (Electrical))

For all these buildings being (re)-inspected, allow only people from out-of-state, with NO business ties to Florida, to do the inspections.
During the Texas power outage the complaint was that someone from out of state sat on the commission and thus had no vested interest in preparedness. If there's a weakness specific to the industry in Florida we ought to address it directly. I have a hard time believing state residents don't have motivation to make communal structures safe & habitable. Consider that their building laws could be too tough in practice, meaning inspectors get overwhelmed and sloppy. Maybe it's condo laws. Or maybe they could use expertise from out-of-state, even foreign. The bottom line is still collapsed structures/safe failure modes.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (nessman)

Not surprising. If the building had major structural issues it would have failed a long time ago. People gotta remember - something like this isn't caused by a single event but a series of events in the days/hours/minutes leading up to the collapse, caused by prolonged deferred / neglected / poorly executed maintenance over a period of many years since the building was first constructed.

Reinforced concrete can last a surprisingly long time with major structural issues. The Hotel New World in Singapore was built in 1971. The engineer forgot to include the dead load (the massive weight of the building itself), calculating only for live load (people, furniture, equipment, etc), resulting in RC columns which had nothing like the required capacity for the building. Over the years, they added large HVAC on the roof and a bank vault on the ground floor. The building kept complaining, it gave clear warning signs, but it did not collapse immediately on any of these significant additions.

It eventually collapsed in 1986, apparently without a triggering event (i.e. no obvious straw breaking the camel's back). One of the columns, which had been cracking for years finally gave up the struggle, everything else was already massively overloaded and cracked, and the entire structure basically just dropped.

That was a massively overloaded RC structure from before they even finished building it, and it took 15 years to collapse. It's conceivable that some major structural issues can take 40 years. That's not to deny the influence of bad maintenance, only to highlight that major structural issues can lurk for decades; until either normal slow degradation, improper maintenance, or some other combination of aging / damage / abuse factors finally lead to failure.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (SFCharlie)

Right, All I think it proves, is that I was right several threads back, to say that a video from a smartphone, whatever, of a security system display, that's out of focus, (and compressed in the phone and again in YouTube) is practically immune to analysis.

Yes. I was able to look at it easier to confirm, but I saw the same thing as I did the first time I viewed it. Crappy detail that makes it very hard to tell, but it still appeared the collapsing floors had dropped a level by the time the video started and the roof was still there.

#### Quote (SFCharlie)

This is why each frame must be registered The smartphone, whatever was moving around quite a bit.

You did a really good job lining them up, but from frame 26 to 27 the right side appeared to drop a bit while the collapsing area appeared to go up a bit. Just shows how crappy the video is.

#### Quote (Red Corona)

The 13th floor should be present over the double pillar, and the right side, but not over the left side (there was no floor 13 there). I'm struggling to see in your version what the visible structure on the left side on that floor is.

I didn't comment on this, but to me it appears to be un-collapsed building behind the falling facade. Nothing about the appearance there makes me re-think the levels. I see the 12 floor balcony and the 2 levels of parapet that have all dropped about 3 floors in the 25-27 frame range in the powerpoint, and there is building visible above that too.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (LionelHutz (Electrical)30 Jul 21 12:55)

but from frame 26 to 27 the right side appeared to drop a bit while the collapsing area appeared to go up a bit.
Thanks for the feedback. Unfortunately, PowerPoint only allows for rotation correction in one degree increments. I've gone back and captured the twitter video. I've dumped out about 200 frames. I'm not going to crop them. I've figured a better way to stabilize the brightness and contrast. I'm still thinking thru a better way to register them, but I'm not sure it's worth the trouble. The jerky movement (which can be seen in another's slow-mo) is not uniform as far as I can tell. Sometimes there are three frames in a row with movement and sometime 5 or so without. The pattern is not totally random, but not consistent like a beat frequency. I don't know?
Anyway Thank!

SF Charlie
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### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

arbitraria

"I don't think they were there only ones" to receive/hear a warning.

Roberto Castillero and Adriana Sarmiento who were staying at the Bluegreen hotel next door across 88th - she took the video of the garage etc.

In his interviews he says there were people out on their balconies (some had come out having heard a "boom") and she was waving n yelling for them to get out, but evidently they didn't understand her. He speaks of actually watching a man fall once the collapse started and they (this couple) had to run to escape the debris.

Waross

No, although there were many elderly living there, many of the Units were rented out and some were used as Airbnbs. That is why many young children died.
Of the collapsed condos (77), my rough count is that 26 of those units were occupied by retirees. 34 Units were empty.

Survivors from the West side do mention a fire alarm, but seems like it went off after the collapse.

But a good question to ask is how are the elderly expected to escape a fire or emergency if elevators are programed to stop and many can't walk down stairs?
Or say handicapped people in wheelchairs??

If their neighbors don't happen by to carry them down (which we know happened on the West side), the rest have to go out to their balconies and hope the fire trucks get there in time?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (nessman)

If the building had major structural issues it would have failed a long time ago.

I guess that just shows that the developer was a visionary.

Why waste money on putting un-needed rebar in when the building will last until maintenance failure brings it down?

spsalso

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

Survivors from the West side do mention a fire alarm, but seems like it went off after the collapse.

I don't know if the fire alarm system is the original one from 1980, but for the original one, a manual pull station, smoke detector, or sprinkler flow switch will transmit a tone alarm for that floor only. After a time delay of 0-10 minutes, if not reset, a general alarm will alert all floors.

Elevators will return to the first floor so passengers can escape and are not sent to the floors that may be on fire. Security personnel and fire personnel have keys to operate the elevator after an alarm for a controlled safe evacuation.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I have looked through SF Charlie’s frames and I see an issue in the basement-first theory. Not enough to rule it out entirely, but something that doesn’t seem to have been addressed much.

In Frames 24-34, the white band on the exterior of the K10/K9.1 column appears not only intact but nearly unchanged IN HEIGHT. The floors above it have collapsed across the entire x10-x11 units, but the K stucco band has barely dropped, if at all.

That’s not to say a collapse of the L and/or M stacks could not have originated in the basement. Clearly, there’s a lot more movement around L and M, and of course that’s where the rubble was seen.

But the white K column stucco band simply did not drop 40 feet, while everything above it did.

And interestingly, if the two flashes are indeed the result of the conduits being cut in the corridor ceilings of 9 and 11, and the upper floors over the x10 units were collapsing while the lower ones were not (yet), that would also explain why we don’t see any flashes on floors 7, 5, or 3.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

Nukeman,

I'm not sure either, if it was the original. I think I saw plans for updating parts of the system, maybe just the sprinkler system.

In one of the very early videos, prob a tiktok... you can hear it.

Regarding the elevators... there is no mention of the security guard doing anything with them, I think they were broken or not working as survivors said the doors were open and shaft was empty.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

But a good question to ask is how are the elderly expected to escape a fire or emergency if elevators are programed to stop and many can't walk down stairs?
Or say handicapped people in wheelchairs??

The egress requirements typically address fire and smoke emergencies - someone in an area with frequent seismic activity may have better information with regard to egress from collapse situations. Those with impaired mobility would be expected to wait for emergency crews to rescue them if an elevator is not available. Code would generally require an area of refuge attached to a fire stair that would function as a safe place to wait for said rescue; this requirement is waived if the structure has an automatic sprinkler system.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

I don't know if it was officially designed / designated as a fire refuge, but CTS had a small open balcony between two fire doors on every floor, as the access to the west stairwell. It could have certainly have served that purpose, being both protected from fire and open air.

The important thing with elevators automatically going into fire service mode is that it disables the hall call stations (so the fire can't call the elevator to the fire floor). It also changes the doors to a special fire mode where they don't open and close automatically and allows a peek function to briefly open them an inch or two and confirm fire and smoke conditions before fully opening them. In essence, it puts the cars into an attendant service mode, and the initial automatic recall to the lobby allows security or firefighters to verify there's nobody trapped in an elevator.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98, arbitraria, Murph 9000)

All good info on how building systems deal with emergencies. Some systems I have installed also had fans on the roof that blew fresh air into the stairwells so people evacuating didn't die of smoke inhalation. Yes, air will feed a fire but the thought is it's more important to save lives than property, and people die from lack of air but the fire doesn't.

Newer systems have addressable initiating devices to pinpoint the fire location and other features is why I questioned if this was the original system. Programing how it alerts people, shuts down AHUs, and elevator recalls hasn't much.

Another reason for the elevator to return to the ground level is so the firemen know where to find it and don't have to wait for it.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

For those looking for grassy knolls in blurry videos...

This is how the building would have looked from the camera's precise perspective, when intact.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Optical98)

But a good question to ask is how are the elderly expected to escape a fire or emergency if elevators are programed to stop and many can't walk down stairs?
Or say handicapped people in wheelchairs??
The elderly and/or handicapped need to consider these things before buying a unit in a tall building. But people don't. They want that nice long range view.

#### Quote (Nukeman948)

Elevators will return to the first floor so passengers can escape and are not sent to the floors that may be on fire.
But what if it's the first floor that's on fire?

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

#### Quote (Great post! Report Jedidad)

But what if it's the first floor that's on fire?

We programed elevators at one hospital I worked on to have an alternative floor as two floors had ground level exits. It is easier to program for different scenarios than it is to convince the money people that it's a good idea.

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

(OP)

#### Quote (rodface (Mechanical)30 Jul 21 18:22)

For those looking for grassy knolls in blurry videos...
This is how the building would have looked from the camera's precise perspective, when intact.
...something's not right about the balconies with concrete (is this what we are calling parapets?) instead of wrought iron railings...See above at:

#### Quote (SFCharlie (Computer)(OP)29 Jul 21 01:55)

I'm trying to corollate what I see in the video with the real building, so I took a couple of snaps in Google Earth Street View

### RE: Miami Beach, Champlain Towers South apartment building collapse, Part 09

> is this what we are calling parapets

Sorry that was me I think! I incorrectly called the full width 12th floor balcony that.

> @Js5180 if the two flashes are indeed the result of the conduits being cut in the corridor ceilings of 9 and 11

If electrics are in odd floors and that's what we think the blue light in x10 stack is then making those on floors 9 and 11 goes with the 'missing 13th floor' interpretation (see my floor correlation pic higher up the thread).

> @rodface This is how the building would have looked from the camera's precise perspective

I think you haven't quite got the angle right, that looks less straight on than the actual footage.

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