Miami Beach, Champlain Towers South apartment building collapse, Part 05
Miami Beach, Champlain Towers South apartment building collapse, Part 05
(OP)
A continuation of our discussion of this failure. Best to read the other threads first to avoid rehashing things already discussed.
Miami Beach, Champlain Towers South apartment building collapse
Miami Beach, Champlain Towers South apartment building collapse, Part 02
Miami Beach, Champlain Towers South apartment building collapse, Part 03
Miami Beach, Champlain Towers South apartment building collapse, Part 04
Miami Beach, Champlain Towers South apartment building collapse
Miami Beach, Champlain Towers South apartment building collapse, Part 02
Miami Beach, Champlain Towers South apartment building collapse, Part 03
Miami Beach, Champlain Towers South apartment building collapse, Part 04
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If we now look at the frame of the TikTok video that Sym P. le has enhanced,
we see a round object inside a squarish frame near column 27 beside a second rectangular object and what appears to be two portions of a broken column. Sym P. le has speculated that the round object inside the squarish frame near column 27 and the second rectangular object to its right are an SUV (possibly a Ford Explorer) positioned head in to parking space 27 that knocked down the column behind it. SFCharlie has speculated that the round object is a washing machine, and JS5180 that is a ventilation fan. Sym P. le has also speculated that the green object is a planter from outside room 111. I believe that the round object inside the squarish frame near column 27 is an air conditioning unit originally installed on the penthouse roof over the middle section of the building. The color even matches the light color of some of the air conditioning units (see photo below). I believe that the rectangular object beside it may be another air conditioning unit and the two rectangular objects adjacent to it may be portions of the parapet for the penthouse roof. I join with warrenslo in believing that the green object is a carrying bag used by the crane to lift materials to the rooftop that was left on the rooftop overnight (see photo below). I believe that these objects slid off the penthouse roof when the roof tilted as a result of the rebars holding the penthouse roof to the front columns were weakened by drilling holes for anchor installation and gave way later during the night as the weaker penthouse roof was heavily loaded with air conditioning units, anchor materials, and roof repairing materials. This event would have happened before the TikTok video was taken seven minutes before the collapse of the entire building, and probably seven minutes before the entire pool deck collapsed. This event would have caused two loud crashing sounds, one when the penthouse roof collapsed onto the roof of floor 12 below, and one when the air conditioning units fell and crashed into the deck below along with sections of the penthouse roof parapet and the green tote bag carrying heavy roofing materials left on the roof overnight by the workers.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
https://apnews.com/article/business-lifestyle-heal...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Really good job on that post. On Round object in tic toc being an a/c compressor unit: not sure but I think I see the fan blades.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
In residential & commercial buildings, almost always pressure is maintained by a "jockey" pump controlled by a pressure sensor. A second pressure sensor with a lower setpoint activates the fire pump, as you described. The flow switches are usually installed and wired to the fire alarm system, to detect activation of the sprinkler system - but they don't control any pumps.
Generally anywhere with over 20 sprinkler heads needs to have a flow switch, I'm surprised there was not one shown in the original sprinkler plans for the garage. Possibly a code violation, depending on what was in force at the time.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Also they are not top heavy, but bottom heavy with the compressor mounted at the bottom, the coil wrapping around horizontally. A small motor at the top of no more than 1/2 hp is on top that weighs about 20 lbs. I just sold the cond fan motor from my 3.5 ton Carrier on ebay.
Certainly all ac units in the collapsed section ended up on the ground.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If the roof collapsed many minutes before the rest of the building, where are the panicked 911 calls from floors 9, 10, and 11?
If there was some cascade of debris coming off of the roof onto the ground below, how was it that no one observed this or reported noises coming from outside of the units?
You reference a narrative about this roof collapse being built by warrenslo and dold… but I don’t recall seeing anything being said by dold to that effect. In fact, they had this to say:
And
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Isn't the view of the TikTok video approximately one column line east of where the AC units and roofing materials would have fell? If your your theory is correct, I think the ac units would be more to the right in the TikTok video???
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Also, your pic of the surveillance photo is mislabled btw.. those lights that are on near the middle of the building must be for the 9th or 10th floor because they're right around where those vertical lines on the building end. It is a bit of a mystery on why the roof and penthouse aren't visible, but they could have fallen down to the 12th or 11th floors in the second before that video starts.
Also, according to that budget doc it does look like they had a security room btw.. they said that equipment was in the Central Recording Station and the photo they seem to show is of a second monitor. If you look at the Israeli 3D models of the site too, it looks like it went through several reconfigurations downstairs.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I think he is referring to the other circular object apart from the gate Champlain "C" . It's been discussed here separately as being possible anything from a washing machine to a truck wheel well.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
As I say all the time, Just because codes allow, or better said, do not prohibit a certain design, does not necessarily mean any particular design that meets code is a good idea. This design appears to have deficiencies and in the very least, fosters progressive failure. It may even be effectively unsuitable for use just because of that one characteristic alone. This design also appears to require intensive maintenance, far and above typical levels, especially given the severe environmental stress it has experienced. At the very least, it was not corrosion resistant in areas that it should have been. This design apparently did not incorporate any progressive failure mitigations. There appears to be no good reason why a design that allowed a pool deck collapse to take out 75% of the building was selected. A simple construction isolation joint might have limited damage to loss of the jacuzzi water.
It is also quite typical that codes do not recognise all design flaws, especially those that are still unknown to us as production line engineers faced with new materials, new fabrication and construction methods and what seems to always be more and more stringent economic limitations. Codes typically only cover things that are within our previous realm of collective experience. Seldom will they be adequate when stretching their provisions to the limits, nor exceeding any established practice of the past, maybe even including an architects wet dream trying to make you design your next slab with 2" thick floor slabs and 50ksi concrete. Will you do it if the numbers work based on present code allowables?
Codes change all the time to address new problems that come up as we move forward. Many of which were totally unexpected. We were designing and fabricating high pressure pipe walls with newer and stronger properties, all permissible under our existing codes at the time, only to realise too late that our quality testing methods were not sensitive to discovering laminations in the steel brought on by the new fabrication techniques. Other materials were found to become brittle under lengthy exposure to hydrogen compounds, especially at higher pressures and temperatures. The pipeline design codes were revised. Some materials were deemed unsuitable and prohibited from further use. Others were required to have different quality control procedures, others were required to be normalised by heat treatment.
It is my highly experienced intuition that is now telling me that we will soon see a number of revisions in building design, maintenance, inspection and occupancy codes due to the results we are talking about here today. Even if for some reason we don't, every structural engineer that's reading these now 5 sections will be thinking about how he/she will react the next time an architect or owner says thin slaps, no drop panels, capitals, or beams. If s/he isn't, it might be time to start.
[IEGeezer, No, I have not learned the whistling language Silbo. That is a specific peculiarity of Isla Gomera. Interesting that you know of it. All of these islands are quite different. I'm on Tenerife, la isla de los chicharreros.]
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
WOW is all I can say about MarkBoB2's outstanding post!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
That would have happened several minutes before the main collapse. When 111 and 611 were hearing noises before they fled the building. Wouldn’t that have all been captured by the security camera as well?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I would get my ASS moving fast
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It was the big HVAC for the common areas, on the red frame spanning E2–H2 and E4–H4 that changed more notably. It also shouldn't have been a major factor, being directly mounted on 4 columns, and not anywhere near the initial collapse. E2 and E4 survived to the end, defiantly poking out of the top of the controlled demolition, as the building dropped slightly ahead of them. They changed it from two separate units to a combined unit, so overall weight should have been in the same ballpark.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
_ _ _ _ _ _ _Studios _ _ _ 1 Bedrooms _ _ _2 Bedrooms _ _ _3 Bedrooms _ _ 4+ Bedrooms
Total: 342 _ _ _0 _ _ _ _ _ _ _ 54 _ _ _ _ _ _ _219 _ _ _ _ _ _ 66 _ _ _ _ _ _ _3
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Is that your guess or are you telling me that the code makes no requirements for the secure mounting of mechanical equipment on the roof in high-velocity hurricane zones because a 3-1/2’ knee wall will keep them from blowing around in 100+ MPH sustained winds? You can’t see it but I’m making my skeptical face. If that’s the case, it will be the most shocking thing I’ve learned today.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I know my unit residential at ground level is not tied down in any fashion. That's beside the point. What are the odds that one unit out of how many on that roof had a degraded or corroded attachment that broke loose considering the claims of neglect elsewhere?? I get your point though. Also it was somehow inferred that the sheer weight of the units played a roll (not by you). I think the weight distribution in the unit was only pointed out to state how easily these would roll or topple if they broke loose. The fact of where it may have ended up is symptomatic or some prior event taking place and nothing more. I think.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Sounds like she heard a thunder noise and saw dust before the building collapsed.. or perhaps that was just the first part of the collapse.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Even in the fringe theory outlined above the inset picture shows that the units were mounted to a rigid frame of some sort above the roof surface.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
1) eyewitness accounts that the pool deck collapsed first, they called it a "sinkhole"
2) the punch through failure of the column/pool deck connections at the the columns. If the building fell first on the pool deck, you'd expect to see shear failure at the impact area instead of widespread "settlement" of the entire deck and several columns that demonstrated punch through.
3) the collapse video shows the face of the building collapsing as one piece, suggesting a failure at the foundation. With a top down failure at the roof, you would see pancaking of the top cascading down to the bottom.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Amazing how fast the authorities act when it affects their livlihood...
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 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Well, the previous owners had the jack leg installer- but mine was not bolted down.
Wind or not- they should be bolted down simply so the lineset is not a main component of the provider of force reacting against the start up torque of the fan motor.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Calling the quality of Miami area installers jack legs is an insult to jack legs.
You know the ol' saying. Tighten her until she starts to loosen, then back it off a quarter.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Great work!
The following images compare the TikTok view to that of the Champlain North tower from Google Earth. It seems that the column between stalls 27 and 28 has been obliterated and perhaps the rebar from the column lays across the entrance aisle. The column at front of 28 (next in line in these images) is known to still be standing having punched through the slab and being visible in the post collapse imagery.
The missing column would be unique in not having punched through and this would be consistent with impact from falling debris. MarkBoB2's comparisons are compelling even if hard to believe.
In the following, I've scrunched the image width to somewhat account for the difference in perspective.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The starting torque requirements for traditional ac induction blower motors is low. You can start them with your little finger if the run capacitor goes bad. From there it's smooth even acceleration. Mine is not bolted down and it does not ever shudder slightly on start up. There is very little internally generated peak force being expressed to the frame. The fan motor torque could never ever move the base or threaten is security.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I am not sure about the entire penthouse roof hinging as a solid slab. If the infamous roof anchors caused something to fail, I think it would just be the cantilevered roof over the balconies and the parapet wall.
That may well be the trigger that caused the mostly agreed upon initial failure of the pool deck. I find it very likely something atypical happened to the pool deck to initiate the failure. As it has been mentioned, once the deck failure began the rest was inevitable.
JR97
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Rheem hold-down strap.
Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
That said, the renovation plans DO show a “jet fan” in that approximate location. I could not find a detail showing what model fans they were, and we don’t know if they were installed or not.
I continue to think that some degree of early damage occurred on the western penthouse roof - these images is from the surveillance camera’s perspective, and includes the camera itself. The drop of this middle area is not well explained in the context of the lights still being on. Both theories need some work, and there isn’t much to prove or disprove.
It’s incorrect to say that it’s impossible because nobody reported falling objects. How many people were watching before the booms?
As for occupants on the upper floors or in x10/x11 above floor 7, we don’t know if there ere any that night. The lack of complaints doesn’t mean there wasn’t an event there.
Finally, a roof collapse could have occurred even seconds before the main collapse, and that would explain the missing parapet. Again, I don’t see how any of these theories can be ruled in or out at this time.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I guess it's a bit more thrilling to think that you can see stuff from the roof on the garage door in the tiktok video even though it's really grainy, but it can easily be explained by stuff that's sitting on the pool deck that we know has collapsed there. If all of those shapes are items from the roof, where are all of the large planters, circular tables, etc from the pool deck. Also, I think you can see the column lying on the ground between 27 and 28 on the floor there, with the top facing towards the southwest and the bottom covered in rubble. It's more obvious in the original video than it is in the lightened photo though, because it's the only thing that's clearly painted white.
Sym P. le, That before garage photo is a bit off too.. the streetview pics from 2011 are a closer perspective and you can just barely see the column towards the top of the screen in that one. I believe they were posted around part 3 or 4 though, so I'm not going to post them again.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Saying it is more likely to be a table ignores the obvious - it just doesn’t look like a table.
As for the green, I think the green in the tiktok is way too artificial and man made to be plants. The fact that an enhanced picture was able to bring it out so easily suggests it is very consistently colored.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
With how much it's been raining down here recently, and how poor the drainage and waterproofing in that area was, I don't find it unlikely at all that there could have easily been 3" of water sitting just under the surface of the pavers. Even as first responders were first getting there, water was puddled up in spots that had yet to spray with hoses and had not had water mains leak on.
How much water weight could potentially be on that slab? Seems likely far more weight than that of any falling AC unit.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
https://files.engineering.com/getfile.aspx?folder=...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
https://files.engineering.com/getfile.aspx?folder=...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The planter soil may have been quite saturated as well.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
For the roof-based theory, it sure seems like there needed to be a chain reaction of components experiencing there own acute, sequential worst case scenarios.
For the deteriorated plaza theory, all it really needed was father time and breakdown of inherently impermanent / imperfect systems.
Something cut this building's legs out from under it. I personally lean towards the plaza deterioration theory. At the same time, the falling roof debris theory isn't an impossibility.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Another possibility: the water in the video wasn’t coming from the sprinkler lines. Didn’t the planters have some sort of automatic watering system? Perhaps the pipe that broke was related to that?
(I’m not necessarily endorsing this theory; just putting it out there as another possibility)
“NOOK-yoo-ler. It’s pronounced NOOK-yoo-ler.”
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
3-4 years ago a contractor from the Miami area hired me to make some planters for a well known hotel down there. Wound up not doing the job, but his plans called for 2ftx2ftx10ft planters with no drainage, and mounting tabs so he could just lag bolt it down to the concrete where they wanted it internally.
I don't think a drainage system was installed prior to, or work had even begun on fixing the issue with the drainage. I'm an hour north of Surfside, and up here, from the 21st to the early hours of the 24th, we received 2.44" of rain, and it's been on the drier side here compared to more south. It's been mostly cloudy too, and water has just been sitting here in puddles. Especially areas where there's a lack of drainage, 3-8" of water easily pools up where allowed. Sloped drainage areas with clogged drains, especially around landscaping day or windy days when lawn debris is everywhere, are all too common.
Even though there is a pipe hanging, that may have absolutely nothing to do with the fire system. (Plus, if the penthouse collapsed first, where were those fire system alerts?)
The slab could have fully cracked through, or even epoxy injection repairs could have failed, allowing the sitting water on top to start to flow through cracks, which could explain what we are seeing. To me it looks like no more than a small amount of water being poured or drained, similar to the amount you'd see coming from a gutter/drain system, not a pressurized system for fire suppression. I've seen those break first hand, and you actually get gushing, not the slow, 80 year old man prostate dribble coming from the upper deck in the tiktok video.
Precision guess work based on information provided by those of questionable knowledge
Aerospace/Industrial/Medical/Structural
SoFla
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
You are building the argument. Tons of water plus junk from the roof may be the difference.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Precision guess work based on information provided by those of questionable knowledge
Aerospace/Industrial/Medical/Structural
SoFla
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I also feel pretty strongly that failure at the area you point out led to the eventual collapse of the building. Start on the basis that the deck collapsed first, and then ask why some parts of the deck simply punched through supporting columns or sheared away from the structure, yet this particular portion of the building collapsed? Then ask, what is different about this area? The answer to that is that this area had a stronger connection to the building than any other area of the pool deck because of the beams supporting the step down terrace. And therefore, the most likely area of the building structure to be impacted by a failing pool deck.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
This would, to some degree, change her view from the balcony.
https://www.reddit.com/r/CatastrophicFailure/comme...
BKNJ
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Let’s look at the column M10 stack - this is next in the row, west of “27”. I’m pretty sure most of us agree this column was compromised and played a major role in the collapse (even if not the trigger).
The roof extends a good bit past M10 - I’m estimating 8 feet. At the edge is a CMU parapet.
If M10 has sunk and M9 has not, then the roof will slant outward. The outer face of the parapet is now inches over the edge of the building.
At this point, doesn’t the parapet now become the weakest link? The rest of the collapse portion, when it falls, is tied together. The parapet is now a few degrees off vertical. It is held on only by a few bars. We saw in the controlled demolition - a section of parapet actually separates from the roof in free fall.
Each foot of the parapet weighs about 288 lbs. Each foot of cantilevered roof, on the south wall, weighs about 900 lbs. And that’s a 6” waterlogged slab which appears to be exactly where some level of roof work was being done. It would take very little “sink” in columns K/L/M to cause that parapet to lean or that cantilevered slab to bounce like a diving board.
The parapet, in my estimation, would almost be expected to break off, even with the slightest drop in one of those column stacks.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Couldn't it also just be caused by a sinkhole under the foundation? If the concrete was leaking water down to the garage from the pool deck too, it seems likely that the foundation was doing the same.. perhaps that caused some damage? It was above limestone. It seems very odd to me that this column collapsed onto it's side, but the column next to it puncture sheered and there's nothing that shows that the pool deck was pulling the collapsed column towards the southwest. It looks like the pool deck just fell straight down.
I found this map which seems to say that it's possible.
Some articles also say that Cassondra was in 410 and not 412 - https://www.usatoday.com/in-depth/graphics/2021/06... (Cached version that doesn't require an account: https://webcache.googleusercontent.com/search?q=ca...)
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Precision guess work based on information provided by those of questionable knowledge
Aerospace/Industrial/Medical/Structural
SoFla
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
So, the pool deck gets super old, it's had it, it collapses to the ground. Somehow causes the entire building to collapse. Right, sure, so then we should find every column still in it's rightful place punching through the pool deck.
There is the opinion that the roof collapsed over the side and slammed into the pool deck. Sure, that's possible, I don't think you can argue either for or against this. Needs more evidence. But, how does the roof crashing into the pool deck, somehow magically destroy a column? It just magically slammed into the exact position on the ground where the column was and Thor's hammered the crap out of it from above?
This isn't obvious, neither of these two could possibly be the initiating event, because we still have a missing column, where is that column? Also, the pool deck above the missing column looks intact right? So, it didn't punch through and then disappear right? It wasn't obliterated by the building falling on top of it. So, what happened to it?
Well, I think this matches with a side collision from a vehicle. You have a vehicle slam into that thing at full speed, and you've got enough of an impact to knock that thing out from under the pool deck. The connection to the pool deck is not much. So, if I am right, then your going to have a dead motorist crushed under the pool deck, inside their vehicle, next to a collapsed column.
But, how exactly does this happen? Well, you think about it, car is coming down a ramp, maybe the driver is tired, being it's late at night, and a foot taps the wrong pedal, and before you know it, it's right through the column. Why is this a difficult concept? It happened to me, old lady next door, she had a V6 she used to park in the backyard under a shady tree. Her meds are making her tired, and she gets in her car, winds the window down, and before she knows it, she's made the car fly 10 meters at speed through a fence and into the next door neighbours garage.
In 10 meters this woman dropping the foot to the floor on grass in her backyard, had managed to cause structural damage to a double bricked garage.
That guys story of "power is out", "left my car down in the garage", "left on my scooter". Something about this seems a bit BS to me. Like, you imagine if the person who did slam into the column, had managed to get out of the area before the collapse, you think they'd want to be honest about the situation, like, yeah, I just killed 150 people by driving drunk / tired into a column.
And, honestly, I've known plenty of people to slam into building columns. My uncle did it in an old BMW once. Wrecked the rear of his car big time. The column stayed in place, due to it supporting a 5 story building. In Australia, our columns are super thick, and honestly, I think these columns were probably very thick as well. Just, I don't think they were rebarred well at the top and maybe at the bottom.
The columns might be super strong, so you'll probably find them intact. I think of all the issues this building had, those columns were not one of them. And you tend to over engineer columns if they are going to be supporting the weight of a building. The columns under the pool deck, looked to be a very similar strength to those under the building. With one exception. The columns under the surviving structure were stronger.
You think maybe when they did the columns under the pool deck, they were thinking of the future? Like, in the future you might want to expand the building above the pool deck? It wouldn't surprise me. Like that pool deck is taking up valuable real estate.
On another note, people say the building is in bad shape, but it doesn't actually look that bad, like you can clearly see a bit of money going into fixing the cosmetic appearance of the building. The boards priorities with repairs seems to be entirely based on increasing condo value. If I owned a condo in an old building and was on the board, I'd probably be doing the same thing, getting the hell out of there.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Thanks for backing me up on that. I've always been an advocate of the pool deck collapse mechanism (ref threads 1 and 2), and have found the roof anchor discussion quite tedious.
Id like to comment on the redundancy of modern PT construction. Current codes require a minimum number of tendons (cables/strands/etc) to pass through the core of the column in each direction. This provides redundancy in the event of a punching shear failure as we see in this collapse. The intent being to prevent the failed slab from dropping its full weight onto the slab below - with obvious consequences.
However, even if Champlain towers south had such a system, it isn't really clear if that would preclude a collapse of this nature. To me (and as presented in the youtube video+translation) it seems that the collapse initiated at the pool deck slab somewhere, and caused some sort of perturbation in the columns supporting the south side of the north wing (can't remember the gridline at the moment) ultimately leading to the column buckling. Most likely, in my opinion, caused by loss of support at pool deck level via pool deck collapse.
I feel like at that point, no amount of redundancy can stop the momentum of 12 stories of concrete frame once it starts moving.
The columns and particularly the slab to column joints are just going to get rubble-ized. Consider the photos that show apparent voids at the floor levels along the height of the column stacks. I have no calculations to back it up, but the slab mix was 3-4 ksi and the lower column mixes were 6-7 ksi if I remember correctly. Really just food for thought, but under impact loading, I would expect more of a crushing failure as opposed to an instability/buckling failure. Which appears to be reflected in many photos. A secondary effect of this (also mentioned in the translated YouTube video) is the rotation of the entire collapsing structure about the vertical axis - read: P-Delta).
And about this RTU anchoring business. Current Florida building code amends and SPECIFICALLY addresses the design wind loads on roof top equipment. I think its factor about a 2.5 in Florida vs a factor of 1.9 for the vanilla IBC (uplift coefficient). You're looking at pressures well in excess of 100-150psf for RTUs in that exposure and height AGL. Nobody would consider shielding from a 3.5ft tall parapet thats 10ft away (...probably). I guess none of that matters if it was installed by some unpermitted jack leg.
Even if it was just loose, i have a really hard time imagining a 250lb residential unit just...falling over...then causing a global collapse of a building.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
One problem with this theory, is that if a car hit missing column, and completely displaced it, the car should probably still be there. And it’s not. It’s the billiard ball or swinging cradle thing.
I think it’s pretty clear that a pool deck collapse weakened the rest of the structure, especially around units x10/x11.
The question is more about what caused an already weak pool deck to collapse. Did it collapse on its own, or was it hit?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If that is a column, the bottom seems to line up well with where a column should be, but it's too covered in rubble to see it. I think if a car had hit it we would see a car here, underneath it or the rubble. But it would have had to hit it with such force.. I don't think a car would be capable of it. And yea, a few stories from the building sound odd.. but that's also how the truth sounds sometimes and they all seem plausible. That guy with the scooter also wasn't the last person in the garage btw, two actors from Argentine were and they had just gotten into the elevator when it went down. They then left the country in a hurry.. but that's also just how rich people act.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Column M11 should be about where the word “both” in your graphic appears.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Note the Column at M11.1 is quite smaller in cross section, possibly 12" x 16" - much more susceptible to a vehicular impact. But if that's what happened, the only way we will ever find out is through surveillance video or a confession.
The thing that's nagging in my mind is the column on the left (M10) is supporting the building and the column on the right (M11.1) is only supporting plaza slab. But since they are connection by a beam, if the column on the right (M11.1) collapsed for some reason, the falling slab would cause the beam to rotate clockwise and put a huge bending moment on the left column (M10). That's a plausible trigger for the subsequent building collapse.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It shows:
the average price for units w/# of bedrooms over the past 24 months
the average price for units w/# of bedrooms times the # of units that size
and
the Total of the average price times # units for all units
SF Charlie
Eng-Tips.com Forum Policies
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
bones206, Interesting, I hadn't noticed that pipe but it does seem like that could be right under the planters in front of 111.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The water coming in, would rust and destroy rebar, but it probably wouldn't damage the columns so much as the connection points? Those connection points are super weak. Concrete sheared off the columns easily. But the columns are still there?
If the basement had a lot of flooding, perhaps the rebar in the foundation connection to the columns is even worse? The water has to go somewhere right? So, a vehicle knocking down a column is impossible? Not even flying down a ramp at full speed? Can we myth bust this? Anyone got an old car and an abandoned parking garage to prove this?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
What production model car is going to gather enough energy to dislodge that column with at most, 85ft of run-up space on slick concrete from a dead stop? The garage entrance gate was closed too, and those things don't just slam shut. No car took out that column, unless both theories are correct, and a car fell off the penthouse roof onto the pool deck.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Precision guess work based on information provided by those of questionable knowledge
Aerospace/Industrial/Medical/Structural
SoFla
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Column M11.1 failure doesn’t have to be the initiating event. That beam could have simply failed at mid span and it would have had the same effect of applying a bending moment on column M10.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Myth busted. Tree still standing after highway speed impact with mini van.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Modern connections are more robust due to the use of stirrups or stud rails or puddling of high strength concrete atop columns (questionable).
The pool deck design had no real shear reinforcement. The design concept was
To design the concrete thickness to handle the shear. Then to design the horizontal top bar for flexural tension, and then place a certain amount of horizontal rebar directly over the column for good measure. This is the same philosophy with modern PT.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
No. It was not "above". It was at the same height. There was not "slamming down on them from above" by the pool deck.
If you disagree, please state the height of the pool deck above the columns.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I am missing your point. I think it's been said there was roofing paper rolls on the roof. Everything fell down, with the roof pieces on the top. I would expect the rolls to be there, on or near the top of the pile.
Please explain why you are surprised.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Now that your mention it, I think I see the rolls of roofing paper in the middle of rubble.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Are there cameras recording the debris removal? Where is it being taken? Is it being keyed in any way to the location where it was found? Are the NIST investigators on site? What are they doing when they are on site?
Did NIST approve of the standing building's destruction? Did NIST collect evidence for their investigation prior to the destruction? How did they do this?
What is the name of the lead investigator? What are the names of the other members of the team (approximately 6, I believe).
Why has it taken over 10 days to hear from these investigators?
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
1994 Northridge earthquake - PT integrity tendons support severely damaged slab:
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I guess I don't believe falling debris from the roof is capable of making an entire column disappear. This to me is something else. Could a car cause a column to dislodge from the top and bottom?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Sorry about that. I wasn't trying to be elusive. After I posted it I realized I left out the context. I meant to post as an ongoing description of what is in the tic tic capture that has more recently been under review. I mean to describe what occurred to me as it appears in that enhanced capture. So that in effect this would describe roof paper rolls in the basement before the main structure collapsed. I meant to look at it as objectively as I could. But what I think I see is roof paper rolls and then as mentioned before in the thread, not far away in the basement is what appears to be a material that is the color of the tarp that was used to cover said rolls. If anyone mentioned the appearance of the actual rolls in the basement before I missed it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Yes, I see that too. I am sure our NIST investigators will, uh, investigate. And perhaps confirm it's rolled roofing.
They are PROFESSIONALS, damn it!
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I see the problem. You said "in the middle of the debris". Debris to me is the big pile at the former building site. You are talking about some debris in the parking area, down the ramp. I think.
Yeah, that surely could be roofing paper. Or something else.
Rest assured, the NIST is on the case!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It's interesting too that it sounds like Cassondra was in 410 and she only described it as a sinkhole under the pool deck, instead of the upstairs parking area as well. It really makes you wonder how extensive it was when she made that call.
Js5180, I think you're underestimating how far apart the lengths would descend from this perspective.. either way, it can easily still be that white object at the bottom of the pile of rubble there.
Thermopile, How would the column end up on top of the planter though? It's also too far back.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
"The left side of image looks like 3 rolls of tar paper all lined up, with slight angle changes between rolls"
That is some quality roofing paper, to remain (semi-)usable after a fall like that. I should get the manufacturer's name.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
On the left is a completely destroyed column supporting a building. As a result of this impact, the building had to be shored up, and a new column constructed to replace it.
Sohel, K.M.A, Al-Jabri, K & Al Abri, A.H.S, 2020. Behavior and design of reinforced concrete building columns subjected to low-velocity car impact. Structures (Oxford), 26, pp.601–616.
"The columns that are located in car parking garages or adjacent to roadways are highly vulnerable to out-of-plane loads imposed by the moving vehicles. The column that is subjected to impact force imposed by a vehicle traveling at high speed may be damaged severely and lose its design strength, which can lead to failure of the column"
"Consequently, this can cause the column to fail in taking the applied loads on it. Therefore, the loads have then shifted to the adjacent columns, where those columns may not be designed to support such additional loads. In the worst case, the failure of the column can lead to a progressive collapse of the affected building."
Can't even make this stuff up.
"At an impact velocity of 40 km/h, Column C300 suffered moderate damage at the crash point as well as at the base of the column (Fig. 9a). However, at an impact velocity of 50 km/h, the column C300 failed by shear near the base of the column (Fig. 9b)."
"Column C400 failed in shear at a car impact velocity of 80 km/h,"
C300 300 × 300 2.6% 3101.8 27.26 4
C400 400 × 400 2.6% 5558.2 25.99 8
C500 500 × 500 2.6% 8685.8 26.54 12
C600 600 × 600 2.6% 12506.0 27.58 16
How thick was M11.1?
It is possible, you can't rule it out. If the connecting rebar at the top and bottom of the column M11.1 was weak as the rest of the pool deck, well, why not? It's hardly a worse possibility then the roof anchors nonsense that has legitimately no eyewitness statements. If there was a column impact anywhere in the garage, then M11.1 seems like the most likely target.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
My dads Royal Monaco S/W with a 400
... provided the engine mounts are good.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If the columns are equally spaced on the plans, then the spacing in a perspective photo would be an equal ratio, not an equal spacing.
For example, in the tiktok, if the distance between the right edge of the shear wall, the end of the ramp pillar, and the "27" pillar is the same, then you can take the pixel counts and extrapolate the next pillar location.
Let's say on the plan, the pillars are 20 ft/20 ft/20 ft/20 ft, and in the perspective, the visible ones are 200-160-128 pixels between them. The next pillar will be 102.4 pixels beyond. That same math would put the M11.1 column left of where you're envisioning:
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
So yes, roof first is still a viable theory
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Rolls of roofing paper?!?! Srsly, the plot thickens!
CMU's??? Whoa!!!
I have an idea, but I need some time to develop it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Anyways, if you take that column and place it on it's side, you can see it lines up pretty well with that white area.
I get those drawings aren't perfect too, but I'm not an artist and they look roughly correct. I think when you look at the negative recoloring of the photo though, that's when it becomes very obvious that there's just one white object on the ground. Not sure what else it could be really if it's not the missing column.
Also, couldn't those bars on the floor just be sprinkler pipes? We know they probably fell down around there too, and there were two of them.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Also, it seems like you can see the rebar and metal sticking up in the spot where that column used to be once you draw it out more in 3D.
Maybe these white rocks are bits of the missing column? Again though, it seems crazy how far they are from where the column was.. this is about a car length and a half away.
Sym P. le, you can find them here - https://surfside.one/public-records-search/ All of the 2021 permits, the 2021 plan, and the preliminary review plans for the 40 year certification are probably worth looking at. The inspector was actually there around 14 hours before it collapsed too - https://www.palmbeachpost.com/story/news/2021/06/2...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Speaking of rebar, does this look like a J-hook or where a J hook was in a section of concrete?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Y’all staring way too hard at that grainy image. You might could begin to see Stikini creeping around behind the columns if you squint just right.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Behind a paywall but you can watch it in Incognito mode
Several closeups from various angles. Hard to make much out, but there could be clues in there.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I'm thinking the actual speed of a vehicle required to destroy this column is less then the 50km/h. Depending on the severity of the damage, much less. If the rebar is brittle as hell, as proven by the punching shears, then I don't think it's a stretch to suggest a car had something to do with this.
Now, if this column gets kicked out at the bottom, the car is probably under the rubble down the back.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
A drunk driver managing to do 30 mph into a column at 0100 is certainly a plausible scenario. So is an octogenarian stomping on the wrong pedal.
It might, however, not be necessary to "destroy" the column. All that's really needed is sufficient damage to initiate failure, which could even be delayed. Hit it hard enough to crack it and empty out the rebar cage a little over a few inches, and it will potentially be severely weakened. Or just push it an inch or two out of alignment and the load pushing down is now also pushing it sideways. There are more subtle scenarios than just suddenly destroying it.
I'm not yet seeing actual evidence to conclusively support either of those failure modes, just throwing that out there that it doesn't necessarily have to be a spectacular hit to set things in motion.
Similarly, if a heavy vehicle overloaded the surface parking deck, it could potentially crack it in the afternoon, but maybe the deck doesn't drop until the slab thermally contracts at 0100 (or some other slow failure mode, like each subsequent vehicle causes the crack to enlarge).
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Yep. Some people are so invested in the "roof-triggered event" theory that they are hanging their argument on imagery that is one step above a Rorschach ink blot.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
They could possibly be from the top of M9.1, the result of severe damage to it when the pool deck and heavy stepped patio beam dropped. The east / right hand side of apartment 711 dropping slightly ahead of full collapse fits with that column failing in the final moments, then spreading out under the building from there.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The missing column from the Tiktok video is really a problem. Nobody has been able to explain it. All the columns under the pool deck, do a punching shear. You can find all of them but the one at the bottom of the ramp. Maybe it's obscured by debris? Maybe it was destroyed by the building collapse? It's just not present. Is it possible for falling debris from the roof to cause it to collapse on it's side? Then again, without the TikTok video, there wouldn't be vision of the missing column.
I know of one person who's backed a car into a column at 20km/h, it was a massive bump even at that low speed. I think people think these columns are super strong. They hold a pool deck up, how strong do they have to be? They might be very strong, but the connections to them aren't going to be that strong at all. Shear at the bottom is what I am thinking. Research itself points to this, with clear lab testing.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
.
Frequency illusion, also known as the Baader–Meinhof phenomenon, is a cognitive bias in which, after noticing something for the first time, there is a tendency to notice it more often, leading someone to believe that it has a high frequency. (a form of selection bias)
Engineers understand this and they have a engineering method to evaluate problems systematically.
Other disasters also point us to this process taking many Months to Years... before they will have the likely answers to what was the cause & contributing factors for this.
Until then, this is a good forum to discuss many theories...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
In which position could the car have come from, with enough speed to obliterate that column and leave it laying towards the west in any way in the way everyone is claiming to see the column?
There's a good chance that column may still be partially, if not fully intact in that video, we just can't see it hidden behind planters, deck furniture, water draining, paver and concrete rubble, and dangling waterproofing membrane.
I'm still saying it looks like water found it's way down a weak point after collecting on top of the membrane. You don't even need a full section to fail, just enough to begin the destruction, that could from the top, match what was described as a sink hole opening up. A slow failure of debris getting swallowed up from the pool deck that spread to the collapse we saw. The TikTok video gives us at most 5 minutes of zoomed in compressed and grainy 380p. You guys are seeing far more detail than is actually there on shitty stills.
This was the section with massive water intrusion issues leading to water pooling on top of the membrane, correct? Not saying the column didn't collapse in anyway, but there's far more likely and explainable reasons as to why, considering the area, the deterioration, and the known issues. It's been very rainy down here. I mean, are we really trying to push aside known damage to an area from years earlier that has yet to be repaired?
Precision guess work based on information provided by those of questionable knowledge
Aerospace/Industrial/Medical/Structural
SoFla
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
1. Picture of one of four bolts holding down a 3.5 ton Carrier (Factory provided holes but the top grill has to be removed to install). Replaced the Carrier w Mitsubishi.
2. Mitsubish Mr Slim heat pump with factory tabs (two on each side) to hold down AC unit. Prior to installing nuts on threaded rod embedded in concrete blocks that elevate the unit above the original slab. Blocks also anchored by rod into original slab.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Surprised that another camera didn't capture in higher resolution the collapse. Hope they find one to dispell roof debris idea easily.
I just posted due to one poster saying AC units are top heavy (they're not and fan motor typ. only weighing 20 lbs with heavier compressor at bottom of unit)) and other posters saying AC units aren't bolted down. Absolutely should be in huricane areas and AC manufacturers have provided mounting holes forever. All units I've been involved with have been bolted down and I'm inland. Commercial building codes require it and I'm sure residential codes in many areas. Just good practice at least to deter copper thieves.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Sorry 4th beam at slab step down.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If the roof collapsed several minutes before the rest of the building, more people from the upper floors would have been woken up (and escaped) as a result. There’s been no indication that that was the case.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
No, analysis shows the whole section has shifted down by the time the video starts. The penthouse level has not collapsed.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
So you are certain that the first available frame of that video isn't just showing the central stack of the structure already in a state of collapse to the tune of about two stories worth of "fall"?
Even with all of the color-coded line overlays, text boxes, and dot-connecting from previous user posts, my eyes aren't drawn to the "roof is the trigger" conclusion. I personally think that there are more plausible (and boring) plaza-level initiating factors than there are roof-level triggers. But it's interesting to see people's different theories.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Thermopile… it’s tedious. I’m more of an Occam’s Razor kind of guy.
I mean these residential AC units for instance that “rolled” through a parapet wall and/or plummeted into a concrete slab at 70 MPH but are still perfectly recognizable in the basement on top of the slab they punched through??
To me it’s somewhat of a waste of effort. I see of lot of ideas that are having “evidence” manufactured to support it. And I’m most concerned about how any of this could have happened under the care/watch of a structural engineering firm that was being paid over a half a million dollars for their services to ensure that the building is safe and structurally sound.
Barring something new/concrete coming out, for the time being I’m content on chalking this up to the planters. Or maybe a vehicle in the garage. Otherwise we are straying into “disgruntled resident with homemade shaped-charges” territory.
This is usually a place that I hope to find my daily dose of rationality.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Since we are all taking turns squinting at the time tok video stills, here’s what I see: planters tilted on their side, with foliage facing the camera (outlined in blue). Planters resting on the plaza slab which has cracked in half. The exposed cracked edge of the slab is facing the camera (outlined in green and hatched) and the darker area below is the bottom of the slab. We see the top of the plaza slab in the foreground (broken edge outlined in green). Red outlines may be remnants of column M11.1 and possibly part of the beam, but I’m less sure about that.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
So I am glad someone has confidence in the PE SI Wizard....
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Nothing stops a Trane.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If the roof went first on the penthouse, there definitely would have been a fire alarm trigger of some sorts. We don't hear that in any of the calls, videos, or survivor testimony.
If the building is already collapsing in the start of the security video, as we know it already is, wouldn't that put the roof of the penthouse at roughly the same angle as it would be had the roof just collapsed first?
Also, is this argument of the roof first also saying that what ever did fall, managed to make it over the roof wall, stay in a fully recognizable shape, and fall in nearly the identical spot it would have been had it been on the roof, all while punching through the slab?
Precision guess work based on information provided by those of questionable knowledge
Aerospace/Industrial/Medical/Structural
SoFla
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
There is evidence that the pool deck collapsed, but there is no evidence as to its cause. It’s also several minutes prior to the main collapse.
There is also evidence, in the very first frames, that the roof parapet has fallen much further than its adjacent slab to the east. That same visual evidence shows that it sheared free of the M column row, while the next portion of the slab to the east stayed up, supported apparently by the M columns.
I don’t think any of the above is disputed, but if it is, please correct me. The above doesn’t mean the roof fell on the pool deck, necessarily, but I’m trying to line up the undisputed facts first.
I am not invested in a particular theory, but what’s problematic to me is that the lights in some units below are still on, despite the suggestion that the x11 units had already fallen 2-3 stories.
What’s also problematic is that Josh/Building Integrity attempted to disprove an early roof event by claiming that the electrical runs are vertical from the basement. That is clearly wrong. The rest of his theory could turn out to be correct, but right now, it’s going to need some maintenance (which I presume he will do as he’s done before with changing facts).
So that leaves us with an unexplained absence of a very specific roof slab and parapet in the early video frames, along with an unexplained pool deck collapse. How did roof slab K/L/M shear so completely from roof slab M/N/O/P at the M column lines, if M10 had sunk several stories?
Yellow arrow points at M boundary between those slab areas:
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The deck had deteriorated to the point that multiple columns punched through simultaneously.
Debris fell from the top of the building and caused the deck to suffer multiple punch through failures.
My disbelief:
An object falling from the top of the building with enough energy to cause a punch-through of 10 or 12 columns may be much more likely to penetrate the rotten concrete of the deck, without causing a complete collapse.
Or, alternately, the falling object would likely penetrate the deck and leave a large hole, whether or not it triggered a complete failure.
Very little of the debris from the collapsing building fell on the pool deck.
Did something from the roof fall onto the pool deck and trigger the collapse?
Possible but highly unlikely.
Comment on the vehicle impact:
It is known that the concrete and the rebar in the columns was severely degraded.
The objections to the vehicle strike theory may be based on a column of normal strength.
These were not normal strength columns.
I don't know what the original safety factor was, but let's assume a safety factor of two.
As the column degrades, the safety factor drops. The higher the safety factor, the longer the time for the factor to drop to one, but with progressive deterioration, eventually the safety factor will drop below one.
With no safety factor it may not require a high energy trigger to cause one column to fail.
That failure will transfer loads to adjacent columns and slab connections with not enough residual safety factor to prevent a punch through.
Could a vehicle, striking a badly corroded, deteriorated column with almost no safety factor have triggered the collapse?
Possible and highly likely.
Or;
Eventually, in the absence of an external trigger, unequal thermal expansion and contraction may have triggered the collapse.
Possible but highly unlikely.
Another thought on the "soft" concrete and a vehicle impact. This is more of a question than a statement.
With the "softer" the concrete, more of the load must be carried by the rebars.
If a vehicle impact crushed the soft concrete, could it also have bent some of the rebar out of the vertical plane and taken the load bearing capacity of the column below the actual load?
Comments invited on this possibility.
I have seen very poor concrete and I have witnessed concrete samples being taken inappropriately. (As the inspector was placing the sample cylinder in the trunk of his car, the mixer operator was spinning the water valve wide open to increase the slump. The test strength of the test sample had no relationship to the actual concrete strength as placed.)
Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
This showed up in my earlier post where he was using less than optimal concrete strength and 3/4" cover for repairs... gotta shake your head sometimes.
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 05
Precision guess work based on information provided by those of questionable knowledge
Aerospace/Industrial/Medical/Structural
SoFla
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Precision guess work based on information provided by those of questionable knowledge
Aerospace/Industrial/Medical/Structural
SoFla
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The penthouse wasn't yet in the plans in which the garage had no flow switch, at least not on the page I posted.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
This is URL I am getting 404- File or Directory not found.
https://townofsurfsidefl.gov/departments-services/...
Have they moved the files to another location, or is site down, or have Politics intervened after reading this forum???
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Mb3928 - Did the alarm EVER go off?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Some deluge systems use open sprinkler heads and a second dry, air pressurized pilot system.
If a head on the pilot system operates, the dropping air pressure allows a water valve to open and supply water to all of the wet sprinkler heads.
Deluge systems are often used for vehicular areas. A typical system only supplies water to the head that has overheated. A deluge system supplies water to a zone including the area of the head that triggered the flow.
A flow switch is not required. The alarm may be generated by a limit switch on a part of the main water valve, and a broken water line may drain accumulated water but it will not initiate the main water flow.
The alarm may also be initiated by a pressure switch responding to the dropping pressure in the pilot line.
This may also start an auxiliary pump.
Don't assume that a broken sprinkler pipe in a parking area will have the same result that would be expected in a building sprinkler system.
Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Is there a reasonable explanation for why half of the column would be smashed into bits if something fell from the roof or if the building suddenly deteriorated beyond some small cracks that day? It seems to make the roof theory the most implausible one. We get a good view of this column in the 2020 tour too and it looks like it's in great shape, same with the columns closest to it. No matter where you think the column is, in the tiktok video it looks like it was completely separated from it's rebar down below. What could even cause that? This column was barely under any load, and the column under load is still standing. Good point on those white rocks too, it would make more sense if they were from column 27.
I think if you look closely you can also see the straight yellow line of paint near the bottom of that column, but that would just place the column even further from where it should be if that's the case. Something more like this, with mostly the top missing. Perhaps the top of it stayed attached to the horizontal column above and that's why we can't see all of it? But I can't quite make sense of it separating from the rebar completely at it's bottom, and it being so far from where it should be. There just isn't enough rubble near it to have pushed the column around at all.
And that surveillance photo isn't proof of much, since the video doesn't start at the beginning of the collapse. It's impossible to know for sure what happened in the seconds before it.. it's just a guessing game when it comes to the roof first theory because there's so little proof that was the case. Most people report only hearing two smash/crash/boom sounds before the building completely collapsed.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
No clue why, but that site was setup a day or two before they took the other one down so it was probably just a migration to a better site for them.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
No more than 1 story. As you have seen the analysis on youtube by Building Integrity, you have seen he accounts for all the upper floors - there is no collapsed penthouse, it is right there in the image. We can't see well enough to see that the parapet wall is still there, but it is not obviously missing.
Josh made an error wrt the electrical wiring, but his statement that one frame later (40 milliseconds?) the lights go off anyway. That doesn't seem unreasonable. To make the roof collapse work, something on the roof has to come loose, jump over the parapet and land at the exact right spot below to weaken the patio deck. That seems far more problematic than explaining the lights staying on a fraction of second longer than might be expected.
Building Integrity also does a great job analysing the roof and showing it was not overloaded. The argument that drilling roof anchors or a proof test weakened the roof is just speculation, there is no evidence. While work on the roof might be a good place to start an investigation, it turns out there is nothing in it and it was indeed coincidence.
The simplest theory that fits the majority of known facts is a collapse initiated in the basement. Making the roof collapse theory work requires too much speculation about events we do not have clear evidence for. It really seems like trying to make the facts fit a theory. At the very least, it is premature based on what we know so far. It's possible the investigation will find a smoking gun in the rubble, but there is just nothing significant enough right now.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I wouldn’t expect to see columns laying intact or even in pieces on the ground. They have rebar at both ends. That isn’t really a likely failure mode for RC columns. If this was a stone church, then yes.
The missing column is curious, but there are many possible explanations for it. First, it could be hidden by all sorts of non-reflective debris, like topsoil or plants. Second, it could be hidden by a hinged piece of slab. The picture is simply too grainy.
And remember - to the extent that I’m suggesting a roof event, I am not suggesting it as a trigger. I am only stating that the absence of the K/L/M roof slab, the in-plane appearance of the floors, and the lights being on all work against the theory that the M column descended first. The answer to that doesn’t lie in the basement pictures but in surveillance video and the roof framing plan.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I know I saw this reported on multiple platforms in the first couple of days afterwards, but it wasn't repeated much as more information came out, I had to go looking go find it.
https://www.washingtonpost.com/nation/2021/06/24/v...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Seriously, is it not possible that the already weakened structure simply failed due to the additional weight of inches of water over the pool deck? It doesn't have to be some freak accident. Would lend to the deck simply falling down, and hinging on columns attached to the building before ultimate failure. Weather data for the area does confirm at least, at the very least, 2" of rain in the days leading up to the collapse. Assuming a lot of it did drain away, and only half an inch is left on the failed waterproofing of the collapsed section. Basing some rough dimensions off of the pool furniture, lets say that's a 63'x49' area.
96,000lbs of water just sitting there, on a weak structure. I do believe between the hours of 9PM and 12PM leading up to the collapse, gusts of wind 30-45 mph were recorded.
I don't really know what damaged, poorly draining, overloaded flat top structure can handle tons of weight constantly collecting on it day in and day out.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
My point is that 1) the 1979 FA riser doesn't show a waterflow alarm of any kind in the garage, 2) there is evidence of significant damage in the garage before the collapse, and 3) there are no reports of a fire alarm going off until during/after the collapse. That's not ironclad, but taken together, those facts are one more piece of evidence lending credence to the initiating event happening in the garage/pool deck area, not anywhere else.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
arbitraria, I heard they were already in the area, and Gabe Nir was the one that called 911 at 1:19 to alert them. The only reports of the fire drill going off seem to be after the collapse. Maybe the security guard pulled it, but it didn't sound across the entire building because of a short in the basement or something?
Demented, If you watch the 2020 tour video.. that's exactly where it was. They were all an equal distance apart and are the same size there. It's definitely missing. We also can't entirely see column 28 even though we know it stayed standing, which hints that the object above it is the pool deck and it hasn't completely collapsed down to the floor there.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I am confident Josh will address the error, but wire and conduit don’t stretch. The vertical feed was a fairly critical part of his analysis. His theory needs to be refactored. He may end up at the same place but you can’t just skip over that part.
As for how a roof collapse would take place, I believe that at some time before the first frame, the penthouse roof collapsed, hinging at the column M line. This could have happened as late as the second before the video starts, but it’s very difficult to prove that it didn’t happen at some point in time. The penthouse roof slab has clearly separated at the M line. Did it shear off and drop straight down? Did it hinge?
Had that event happened independently of the main collapse, the parapet wall was definitely a weak link and it would provide enough energy to damage the pool deck in the manner we see and then weaken the beam between 10 and 11.1. In fact, if there had simply been a strong enough vibration nearby, I’d expect the parapet to be the first major piece to fall, owing to its position way out on the cantilever.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Anchors don’t seem to be installed very good.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Designed for? A lot of sand on top of it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
JR97.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
What I found interesting in the above photo:
Yes, the two heavy rebars meet at the joint. Perhaps it is acceptable practice to do this for one of four bars passing through vertically? Concrete guys, of which I am not, would know.
But also:
It was posted on June 30. That means that some or all of the parts of the building were being relatively carefully kept off site, for evaluation. As you would expect, but ya never know....
Also, of course was the amount of rebar going horizontally (formerly) through the joint. I can see only one piece coming out of the (now) top, with no places evident where it had been snapped off cleanly. This then looks like one piece of bar where there should have been six. The facing side seems to be similar. Again, perhaps the location of this particular joint only demanded a small amount of rebar. Concrete guys?
So far, this is the ONLY photograph that I've seen with good definition and up close to the subject.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
What I see with the cue, is I see top portion of column 28 upside down, standing on j-Hook rebars near corners.
Anybody else?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If this 5 seconds of zoom in is the only proof currently of that column being missing, I think we need to all take the missing column theory with a grain of salt.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
update: Definitely gate bars are giving me an illusion of the vertical column corners, so not sure anymore what I see
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If you squiint really really really hard at the tiktok video, lights and shadows might make some sense.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I would agree - if there was hinging that didn’t break the floor completely off, the power still reaches the unit. The other possibility is that there is much more hinging along maybe the 8 columns than we realize. In other words, the corridor was intact, the southern side of the units hinged downward, but there was still a connection.
The wire to the unit panels is unlikely to be cable and more likely to be conduit with 2-3 wires in it. I don’t believe, from the pictures, that the conduit was embedded. The corridors had drop ceilings, and the conduit comes through the shear wall just below the slab, according to the pictures.
I’d be curious to see a diagram that keeps the conduit intact for a few seconds.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Well I think I see j shaped rebar, but then it's all subjective. I have changed my mind on the roof paper rolls. "They" seem to be inflection of the enhancement level shift on what is really the edge of the fallen slab in shadow. But what I "see" now is the base vertically of the broken (missing) missing column where it should be with sheer damage at about the height of a car bumper , or slightly higher - where it ends. But like has been said it's grainy. Perhaps someone could enhance with the intent of bring out that detail.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It's still interesting that if the collapse happened like some people are speculating the fire alarm system didn't sound. I obviously don't know the codes in Miami but most places require annual system checks where flow switches are tested to ensure that the alarm will sound, this is done by opening a test valve at the end of the line.
I still can't get over that fact that everybody is seen so much in these pictures. They are just seeing what they believe supports their hypothesis of how the collapse started. We have no definitive facts at this time kindness what the sequence of events was. Even the information we have from tenants is only speculative because it's a proven fact that people are not good witnesses in many cases. Especially in a state of panic I don't remember the sequence, timing or other facts of the event.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
agentparasite about a week ago. The giggle at 1:30, the mention of "low maintenance" in the sales pitch at the end -- it's all sickening. 15:20 on is particularly insulting to viewers. "Don't be afraid of condos." "Bring your flip-flops!" They get 6% of the project cost to take some photos and unlock the door to "show" the property. They pretend to be legal experts, but they write themselves out of almost all responsibility by passing that on to the sellers and buyers.https://youtu.be/MFTRfsRTpZE
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I have a nearly solid 72" fence around my backyard. It does not prevent wind from blowing things on my patio away during tropical storms, not to mention hurricanes.
Having said that, has anyone done an overturning analysis of the HVAC units? Aren't they fairly heavy and most of the weight is at the bottom?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
What I find interesting about this picture is that the anchor on the left side still has concrete attacks to it whereas the one on the right doesn't. I didn't see any documentation about what type of anchor they were using but the left one certainly looks like they were using a epoxy type anchoring system and the one on the right doesn't. Epoxy based anchoring systems are designed to be stronger than the concrete which obviously with the case here. Normally you would expect a large hunk of concrete to still be attached to the anchor but we are only seeing may be 1/4"-1/2" of concrete still attached which tells me that the concrete itself was extremely weak and deteriorating. I really can't think of a good reasons that we are not seeing anything attached to the right hand anchor of the possibility that they just stuck it in the hole without any epoxy!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It's taken from the north side, but you're seeing all the way through to the south side. On the left of the ramp, the full height wall is the stairwell, and the far side is aligned with the central corridor. The column at the end of the half wall is M8, in the middle of the south side apartments. The column beyond that is M9.1, and the southern wall of the building. The pipe break is roughly in line with the southern wall, below the x11 apartment stack balconies.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The building was Three phase Y, 208V/120V.
Leaving out the penthouses, each unit had a 125A main breaker.
Each unit had a 208V electric range, water heater, AC/heat [?], and optional dryer. Plus, of course, various 120V equipment.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Just watched the video, and agree with you those white spots are stationary objects. But I still see the water level the same as in the photo.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Sym P. Le did a nice job earlier showing the perspective of where we would expect to see column M11.1. It's pretty much exactly where I see it broken into multiple pieces. It's not the exact angle or perspective, so it's slightly off, but it leaves little doubt in my mind that we are seeing the remains of column M11.1.
Also note you can see the white license plate of the same car in both photos.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I've been following y'all along these threads for a few days now. As we're real curious as to what's beyond the parking garage gate, I took a look at the 40 Yr Review Plans. I noticed there's several pages regarding the adding of a new Generator and Fire Pump, and along with that the need to reinforce the Generator Room floor because the new equipment is quite a bit heavier.
Do we know if this work was completed? Because the Generator room is directly over the Garage Ramp.
Link
Link
Link
Link
This last link reflects new piping which I believe was added and we see them here:
Link
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
(1) We need an interview with Eric Zion AND his wife Tamar in the days after the collapse. This is the man who with his wife arrived home from a trip at 10:30 pm and then immediately left to check into a hotel. He came back and spent an extended amount of time gathering things for an overnight at a hotel, when presumably he already had his toothbrush in his suitcase!
(2) What car was he driving? What was its condition, prior to the demo of the remaining portion of Champlain Towers South? What space was it parked in?
(3) Which hotel did he check into? Did he tell the clerk why he was there? Did he seem nervous? Would he have to pay for parking at that hotel? Did he have another vehicle parked on the street nearby that he switched with the car that crashed into the column?
(4)
(5)
(6) Here's the timeline and some details from Reddit:
Think about this scenario: Eric Zion arrives home, is tired, and in parking slams into a column (brake/accelerator mixup -- happens all the time). Column falls, but not on his car. He leaves for a hotel because it doesn't take Einstein's son (a civil engineer) to figure out that a building that is missing a column in the garage is unsafe. He checks into hotel, but wants some of his valuables from his apartment. You know, the evacuation files, jewelry, mementos of his parents, etc. So he goes back and leaves car, then departs for the safety of a hotel on his scooter.
He was probably just hoping that he would not be blamed for crashing into the column. I'm sure he'd be charged about $15,000 by the condo board to replace it, and he may have been held liable for displacing residents once the damage was noticed. Who can afford that? He probably didn't want to pay for the property damage, even with insurance. He may have hoped that the column was not visible on the security cams, and it probably wasn't, based on descriptions of the system and it's focus on entrances and elevators, etc.
Thanks to all who kept coming back to wonder about "the guy who left earlier in the evening to check into a hotel". I hope investigators are exploring the potential precipitating event of a crash into a column.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It seems plausible that the missing column could be hiding under the large planter area though.. although it makes no sense that it was pulled in that direction when we know nothing collapsed over there. But I'm definitely not a structural engineer.
NOLAscience, can we avoid the witch hunts in this forum? Leave that part to the cops. It's one thing to suggest that a car crashed into it, but it's another thing to start throwing names around. We know almost nothing about these people.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Nobody is driving a car anywhere after slamming into a column at 40 - 50 km/h.
First the crumple zone will have wrecked the engine. Its not going anywhere. So I dunno if he did it or not.
People keep drawing M11.1 as being the same size as M10. Its not. Look at the building drawings. Its 12x16. Its 4 inches thinner on the side that would make it dangerous to a ramp collision.
I cited a real study which tested vehicle impacts with columns. 12 inch / 30cm column was bottom sheared at 50km/h. Thats ideal strength concrete. I think a car could damage this column at a slower speed.
The ramp is 64 feet in length. The column is another 40 feet away. How fast can a car accelerate down the ramp into a column? Its almost precise. The vehicle would continue beyond the impact. Somewhere down the back?
Debris from roof is incapable of destroying M11.1 a vehicle however is. Proven by real testing data. 50km/h is all it takes to bottom shear 30cm column.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
They overlay perfectly then too, and it's pretty obvious about where the column was, and 28:
But yea.. it's sloppy and I don't really like that way of drawing it out myself. The way this is flattening the image makes the CTN garage columns much skinnier in this pic than they actually were too, so it only marks the center of the column.
Crazy enough too, I compared it to my earlier drawing and it's perfectly centered.. I wasn't actually expecting that because this style of drawing is so sloppy.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I kind of buy what you're showing for the alignment. Just for argument's sake, what if column M11.1 broke and toppled to the right? Couldn't that conceivably match what I outlined as the broken sections of M11.1?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Ok, it didn't take out a column (though in the condition these columns were in, who knows), but perhaps it jarred the column and the (1) insufficient rebar that has been deteriorated over time, (2) lack of drop panel and additional rebar connecting column to deck, (3) overloaded deck (from heavy vehicles and water from recent rains in 3" of pool deck over waterproofing collapsed a slab, or at least created a crack. He says to himself, "I am not sleeping in this building tonight."
"Power was out in my unit" is just his cover story for not sleeping in the building. I bet the power company can verify if power was out to that unit before 11:00 pm.
Maybe he just saw the planter had fallen from the pool deck into the parking garage, and he said, "I'm not sleeping in this building. It's falling apart." BUT he didn't warn anyone and he doesn't want to catch hell for that.
His current home address is in NYC. That is a two-day drive. Makes sense that he may have been tired after driving for two days and arriving at 10:30 pm.
EDIT TO ADD: His home address is important if this is where he was returning from. I didn't invent this information. It came from https://www.fastpeoplesearch.com/ .
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
And hm.. it seems too far back in the room to be M11.1/the missing column? I can't quite make sense of it laying across the top of the planter from the other side if it is M11.1. Seems like it'd make more sense that it's under the planter/slab and out of sight.. or it's that white object laying on the ground to the right. I'm sort of convinced that those two pieces of broken column or slab aren't actually the same column and they just look like they are from this angle.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
And fair enough.. I figured horizontal column/beam is all easy to understand language but perhaps not heh.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The angle of the planters (what I believe are the planters) leads me to conclude the slab failed around the 1'-11" elevation drop at the edge of the long planter. The slab would have hinged along grid 11.1 and dropped to the shape of a ramp. That would explain why some of the planters look high up in the photo. Then maybe column M11.1 buckled and fell to the right after the initial slab collapse.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
See the column inbetween parking spots 27 and 28?
This column is M11.1 its the first column not under the building structure. Which is why its got the .1 at the end. Can you see how its rectangular in dimensions? Its 12 inchs by 16 inches.
It has a tri shaped piling under it into the ground. At the top a beam connects it with M10 along the roof. Which is under the planter boxes.
So on vehicle collisions, its normally the bottom which shears out due to the vehicle being low to ground. So perhaps the beam further pushes the shear at the bottom by holding extra strong at the top?
Also someone should be able to answer whether there is a cold joint between piling and column. This and rusted rebar at the bottom make the bottom shear a high probability.
Maybe car impacts at 10:30pm but takes hours to propagate? Makes sense with Unit 111. Slowly the deck fails until complete collapse?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
No one knew the building would collapse too, and leaving your smashed up car behind as evidence without ever calling the cops basically proves you're not innocent.. most people would never take that risk on the chances the building might collapse and destroy the evidence. It's all too far fetched.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Maybe the car hit a column that we cannot see, and that caused the deck above to shear off and fall, tugging on the column that seems to be missing in the TikTok image, and pulling it over. Just an idea.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Eric smashes his car into a column that's GOING to fail, but doesn't yet. Or he'd be jelly. Then, once he's safely out of squishability range, down it comes.
Wow, buy a lottery ticket NOW!
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
This place was built in 1981. Tankless water heaters were as uncommon as mobile phones in those days. And I found a water heater in an image of the remaining structure. See:
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
In the TikTok video, all there is, I believe, is the initial stages of the slab collapse, prior to any other collapse, just around or before the M11.1 column. That is why we cannot see the column hidden behind the fallen planters, pool chairs/tables, and upper deck rubble. Some of the upper deck still on and hanging to what little reinforcement is there. This is just above a planter drain location and near a main deck drain that was known to be partially inop and was leaving standing water above the area in the video days before, which in itself is a massive level of water to just be sitting there given it is known to be leaking through and just sitting on the waterproofing membrane. Given that Cassie called to tell her husband of the sinkhole, it seems it wasn't such a huge thing at the time, which also lines up with just some simple construction noises and bangs from below people heard. The Tiktok video then ends here as they go to the other vantage spot but everything happened so quickly, the building was down before the phone was out recording again. This is likely around the time Cassie then started saying the ground was shaking, screams, the deck fully falls, down comes the supporting structure, and call ends. Almost lines up with what we see in the ring cam video.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Can't argue with picture of tank in debris. Only thing is that water heaters only last 10 years or so so that water heaters in each condo have probably been replaced at least 3 or 4 times. Some condos could have tankless units when replaced if electric service is a least 200A.
My house was built in the 60's, had at least three 40gal electric water heaters, then a heat pump wtr heater w 80 gallon tank, then five years ago a 21 kW tankless. The heat pump water heater worked best. Tankless not enough capacity even at 100A, 21kW.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Nobody can explain the loss of the column. It should be a puncture shear like the rest. There is no explainable reason other then out of plane vehicle impact with a column carrying axial load.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
We can hope there are many more elements preserved as this one was, because they all are needed to fit the puzzle together. In this failure, most slabs appear to have slipped down the columns like kebabs on a skewer. The column in the photo should have at least some of the slab still sticking to the concrete of the column. A 6 inch slab failing in diagonal tension should leave a cone of concrete 6" out from the column at slab top and tapering to face of column at the bottom of slab, This one just slipped through.
Or - was the column bar torch cut toclear other reinforcing for removal? It would seem more practical to cut the slab reinforcing.
Is that a pour joint in the column section just before the end of the bar on the left? There should be a pour joint at the bottom of the slab and at the top of the slab.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Looks like some pool deck remodeling done around 2013? PVC pipes topside? Maybe the drains were being fixed? Planters still has palm trees here. Palm trees were changed sometime in Q4 of 2017. (Image grabbed using Google earth Date and Time filter)
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
(Back in the USSA)
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
https://www.youtube.com/watch?v=PEPyE2h6P4k
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I only listed the street name, and this info is available in a thread on Reddit, and it is public record, which is where the Redditor got it. It's no big deal.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I support this theory, to the extent that it may be a possibility, and I don't care about any other forums or YouTubers. The possibility cannot yet be ruled out, and we will continue to look for evidence that shows that it happened. If we find none, ever, and we find a plausible explanation for what might have been the proximal cause of the collapse, we will come to the conclusion that a vehicle impact was unlikely to be the cause. However, we accept that, as in many plane crashes, experts continue to debate causes long after reports have been filed away.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Key word "if" ^^
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
- Eric and Tamara Zion (went to stay at a hotel)
- Sara, Gabe, and Chani Nir (111)
- Nicolas Vazquez and Gimena Accardi (parked immediately before the garage collapse)
- Adriana Sarmiento and Roberto Castillero
(video of the garage rubble)
The sources are linked in the right column.**************
Edited. Please scroll down for v2.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
https://vm.tiktok.com/ZMdasA62E/
I wish someone could edit this video and just show the garage opening. Remove all the rest and just play the video with all of the motion removed.
Here's my screenshot. Sorry about the TikTok "Play" button. The image is a bit clearer in the attached downloadable file in my next post.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Is there any chance that this is a brittle failure of the rebar? I can't imagine that the contractor did not lap splice the rebar at all.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Do we know where all of these people were parking? It would discredit my theory. Which is important. If stuff was occurring in the building, it was happening around 12:30. There are people coming and going around this time. I'm sure they would have seen a column damaged right? Unit 111 says 12:30, work sounds like it's coming from above. So, this fits in with the roof. But, if it was coming from below, might she not still think it was coming from above? Given that sound would reverberate up the columns around her apartment? You probably won't hear sounds from the parking garage right?
Where exactly do the parking spots line up with the apartments?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Keep in mind too that the only testimonies we've heard are the people who've talked to reporters, and most likely there were other people there that only spoke to police, or no one at all. I'll take a look at the video tonight and see if I can edit it down, but I can't be in this forum if this turns into a witch hunt or if we continue to dox people.. it's way too close to illegal activities that I can't be a part of.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
As I look closer, it appears the left bar tucks under the right bar and may extend some distance into the right section of concrete, and that would be expected.
This part of the detail may be OK. A bit of chipping could confirm this.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If memory serves me right, on some TV show the journo said they were staying in 308 and their parking spot was "on the left" of the unit (left relative to what exactly? I don't know). Thus I wonder if the first noise they heard but didn't recognize was already the deck collapsing into the level below, but as it happened it was hidden from their line of sight (say, if the elevator block was in-between), or if it was another noise from the building, much like the undefined knocking some people had heard some time earlier, but when they stopped at the ground floor, dust was already flying. I'm having a hard time piecing together all the timelines right now (from the various survivor testimonies and videos) and making sense of the different noises and their respective times.
Let me grab the link s if I can find them again...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
This here is the message directly from the guy himself instead: https://youtu.be/yThHXikBav0
If anyone has a better graap of Spanish that what I could string together in the previous message, please go right ahead...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
As I stated earlier, each unit had a 125A 208V service.
And you really should try not to make up quotes and/or poster's usernames. If you are that sloppy with something that can be checked, it implies the same for all your reasoning.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The use of stainless steel to support a ceiling over an indoor pool sounds like a good idea, right? Not so much.
https://corrosion-doctors.org/Forms-SCC/swimming.h...
To bring this into focus with the present topic, it is common to spec stainless expansion bolts when exposed to weather. Is that a good idea in a seaside environment?
If this is too far astray just trash it. I will understand.
Thanks,
Vance
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
As for the roof collapse/falling theories. Why didn't the presumably motion activated camera recording start sooner and possibly catch some of the roof falling? If the roof failed and caused the pool deck damage in that tiktok video then that camera should have been triggered by that failure and been recording long before the building started to collapse.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It would be good to hold final determinations until the member is identified.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Perhaps it’s easier to use the original video without the edits added for TikTok?
https://youtu.be/ngyKmBjIZig
The background commentary is interesting. Vehicle and building alarms are sounding but it’s extremely difficult to make out audibly.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
This isn’t perfect. But it’s an improvement maybe.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Sorry...I haven't yet found any info on parking space assignments.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Some stainless is susceptible to chloride attack... have to check with a materials dude...
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 05
Here is the thing, this area is a warm climate area? See, I don't know anyone who would evacuate a family out of an apartment just because the electricity wasn't on. I know a family who live in a real massive house in a cold area in the hills of NE Melbourne, and you know, tree's falling on power lines and nobody can get cars in and out of the area due to closed roads, and they had insurance which enabled them to end up in a hotel. But, I'm guessing this family in this tower hasn't got a hope of claiming insurance for the hotel stay.
It seems a little weird. Oh honey, the powers out again, better go stay in that cheap hotel again. I mean, did the guy even talk to security? Did he make a complaint about the power? Is it weird that he has no power? Come on, really? He's got the worlds most lottery ticket excuse for not being inside a building that has killed 150 people right?
This couple in the elevator right? I mean, they probably had tickets booked to return somewhere? They might not have wanted to stay in town and give an eyewitness account of the incident? I mean, did they have a vehicle? Where is the vehicle? Is it a rental? I dunno about anyone here, but if I slammed a rental vehicle into a buildings column and the entire thing was starting to rain white cement and broken rain water from the pipes, I bet you won't find me thinking twice about trying to get an early flight out of there right?
Seems the people in the garage have literally nothing to say about a falling pool deck and potential damaged column. I'd probably notice a column sitting on it's side 40 foot away from the ramp on the left. I don't think you could miss the thing. So many details and so little eyewitness accounts.
You know, then there is the other side of this, the condo owners association has all the money right? The last thing I'd want to report is someone crashing their car into a building column. I'd want all the blame sitting on the condo board. That's going to be the thing that gets the lawsuits settled in a flash. Driver hitting column equals no massive pay outs.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
You can see the condensation cloud formed by the gas spewing from the broken freon lines as the unit tumbles in its flight to the southwest out of view of the camera.
This flying compressor should give us an idea of the amount of force required to break the gas lines. I think it's very unlikely a unit falling of a stand as the penthouse roof slab collapsed would experience enough force to break the freon lines. The dangling units shows they're pretty strong, but being launched will break them.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I suspect the camera has a sensitivity setting, as many motion activated cameras do. In the video you can see foliage swaying in the wind within a foot or two of the camera. You would have to have the sensitivity turned down to a minimum to avoid it being constantly triggered by that foliage movement. Thus it probably took the motion of a full building collapse to rouse it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I've also noticed that some of the lights appear to go out in synch with the blue flashes going out, but not necessarily the ones directly horizontal to them. Someone mentioned three phases. Are different floors on different phases? Would this mean that appliances like stoves and dryers are 208v, instead of 240v? Would this also mean that every third floor is the same phase, or is that unpredictable?
(EDIT: added arrow)
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Some interesting things I noticed.. there is a flashing light on the left wall, so clearly the fire alarm did go off. It looks like the reflection of a strobe light to me. Also, I think on the bottom part of that broken column it looks yellow and changes color in a few frames.. I'm pretty sure we're seeing the bottom of column 28/M12.1 there and it isn't attached to that horizontal broken slab/column/beam.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Includes updates to the Nico Vazquez/Gimena Accardi details per the videos cited by emtv. They were staying in 308, they parked in the garage "to the left" of 308, they heard a loud cracking sound (previous translations have called this a creaking sound) a few seconds before they got on the elevator, when they exited the elevator in the lobby, they saw dust and smoke and "sunken cars." They ran from the lobby with a few other people, and then the building collapsed.
NOTE: Other than Adriana Sarmiento, none of the witness interviews I have so far found mention seeing any garage damage.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Personally I hope the parking space info doesn't get out, as this is only going to encourage people to harass them. I'm sorry, but you guys aren't going to catch someone online that the cops have somehow missed. This might be a better discussion for reddit, not an engineering forum.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The swim lane shows that that the Zions, Vazquez/Accardi, and possibly also Sara Nir parked in the garage near the time it failed, and did not mention seeing any indication of an accident or damage. The only witness who reported damage in the garage is Adriana Sarmiento, who shot the video of the rubble.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If that account is true, it would indicate a larger area of initial collapse of the plaza slab, to include the area where cars are parked. As opposed to a more localized collapse in the vicinity of the planters/column M11.1.
Do you guys agree with that line of thinking?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If you drive right past a fresh pile of broken concrete in your garage, and then the building falls down, you might think to bring it up.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Both Sara Nir and Nico Vazquez said that they saw cars. Sara said they were sticking up, and Nico said they were “sunken,” although this may be a bad translation…maybe somebody could check that…the links are in emtv’s post above and in the swim lane.
Anyhow, two witnesses saw cars, so I was thinking that implied they were seeing the surface parking lot had collapsed.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
MaudSTL, I think this progressed a lot quicker than you think. It sounds like the entire collapse starting with that pile of rubble in the garage took about 3-5 minutes total. It sounds like they were in the elevator at the start of that, so they probably saw nothing. They couldn't have driven past the rubble, as it would have been in their way on the way to the elevators.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Exactly my point. Vazquez didn’t mention any collapsed columns, and he couldn’t have driven to his parking space if the rubble Sarmiento videoed had already blocked the entrance ramp. Based on his description, which I hope someone with good Spanish will translate, the garage collapse on the ramp happened behind Vazquez/Accardi, as they were about to get into the elevator. But when they exited the elevator into the lobby, he talks about seeing smoke, dust, and “sunken cars,” and hearing auto alarms before they ran out of the building. He says it all happened within a few minutes.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The Argentina group actually said they went up to the 2nd floor in some news report, before the elevator was recalled to the lobby.. so there's a bit more time I think between the events too btw.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Link
…and also, from the same WaPo piece, it looks like one of the Nirs noticed Vazquez and Accardi by the elevator.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The addresses of people who lived in the fallen building is not stalking or doxing. I mean, if one of these people in the swim lane turns out to have a car that has a giant gapping hole in the front. Surely that's evidence right?
I'm just saying, someone if they hit that column, knows too much, and isn't interested in coming forward. But if someone can get eyes on which vehicle they drove into the building, well, maybe that can be a bypass of their honesty.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Asking about assigned parking spots is what I'd call unethical instead. Imagine a completely innocent person is parked in spot 27 that has a strange story but didn't cause the collapse, and ends up being stalked and harassed because of our research.. that gets you into an illegal territory no matter if you want to call it doxing or not. Some of us have serious careers that we need to worry about, and we can't be attached to any sort of witch hunt. There's absolutely nothing that even backs up this silly car theory. The roof theory is even more plausible than it is.
You are not going to gather any good evidence against anyone online either.. and it's silly to think that's even possible. This forum is about engineering, so it doesn't matter who hit the column.. we're just discussing what could have happened with the building. We can't get into a territory where we start placing blame, or anyone professional is going to have to leave the conversation. Leave that for the police.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
They heard noises when going up the elevator to the lobby arriving into a cloud of smoke and dust. Vasquez mentions hearing two times, more thundering noises. He only direction he mentions of these noises was from the parking area.
According to his account, as the text on bones206 06:50 post confirms, it would appear that Vasquez only heard, but did not actually see any damages to the parking area at that time, because that says, "There we now understand that part of what was the parking area had fallen, with many cars sunk."
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Also, I don't get how those garage lights are still on if that part of the garage is actually collapsed.. I sort of doubt that's the case. It's far too bright to be moonlight. If Cassondra was in 410 and she saw the pool deck collapse from the edge of 111 to the opposite edge by the car parking lot.. there's no way she would have stopped to call her husband too.. it just doesn't really fit.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
The second was sent to various news outlets and the NYPost version posted above is vertically cropped. A fuller version is at USAToday: https://www.usatoday.com/videos/news/nation/2021/0...
The difference aside from wider angle and a bit less resolution is they were actually taken at different times - listen to the audio - and at slightly different angles just 3-4 inches apart - observe the parking space # on the column. What takes me back is that a little less data makes that circular "washing machine" below the gate marquee appear as an irregular shape. I think that speaks to the perils of overly enhancing a compressed video frame.
Additionally, several here have suggested the blue-greenish tint in some of the debris may be part of a construction bag used to hold roofing paper, or even planter material. I think that given the "harsh" fluorescent lighting washing out most colors they are more likely the bright patio chairs outside apt 111 that Sara Nir photographed. They appear in the Washington Post article recently linked:
https://archive.ph/ftQTW/a0d19d141755b8de32ec3ef00... Unfortunately I haven't yet found a better view of what is immediately south of column 27 that could block our view of 27-28.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
microwizard, The reason why there are so many different disciplines in here is actually to make it easier for the structural engineers.. it's difficult for lots of them to edit videos, work on photo imagery, hunt through and find all of the endless documents, etc. There were also a lot of questions about the security equipment in the last thread that none of them were able to answer.. which I think brought a lot of us computer guys in here. I think the reason why it's less informative now is because no new information has come out in a few weeks now. There's nothing unprofessional about reanalyzing the little data we have, come on. If you want an expert opinion, go watch the news.. that's never a good thing to search for online lol
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Thanks for the post. These details are not too small and are otherwise easily missed.
Perhaps some don't appreciate brainstorming. It can be tedious. The purpose of enhancing video is to assist in the evaluation, no more, no less.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Likely a reflection off a wall. In other videos that are poorly lit, cropped to hell, condensed, and squinted at from before the collapse, similar color glows can be seen on the ground and walls. Appears to be the wall just before the hot tub.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Collapse sending a shockwave down the columns until it transfers the load to the top of the M11.1 column, causing it to overweight to failure?
Edit: Original link to source where I found the image. Actual source and date unknown.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
https://www.latimes.com/world-nation/story/2021-07...
"On their last phone call, the day before the tower collapsed, she told him she didn’t sleep well because she was woken up at 3 or 4 a.m. as the building made loud creaking noises."
In a different interview, Pablo said that his mother had told him that the "creaking noise" she heard was so disturbing that she couldn't go back to sleep.
Guess where Elena Blasser lived in the building.
Yes, 1211 (edit: this penthouse is listed as PH-11 and is the x11 apartment layout of the 12th story penthouse floor). The apartment directly below the section of the penthouse suspected of having a roof collapse. What are the odds. A "creaking noise" so loud and disturbing that it woke her up in the middle of the night, less than 24 hours before the building collapsed. A noise that coincided with questionable work by the roofing contractors on the penthouse roof above her.
I think the recovery team is going to find a parapet in the garage, mixed in with debris from the planter it punched its way through. I also wanted to note that the roof scupper in this parapet is also directly above the planter. For 40 years, that roof scupper was inundating the planter and nearby pool deck with water every time there was heavy rainfall. It had actually rained nearly 2.5 inches in the days before the collapse, which is a potential source for all the water pooled on the garage floor.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Three phase supplies are either provided in 460V or 208V. I'm sure each floor would be the same, as providing different phases on different floors would be impractical and confusing. In this case its apparently 208V. The good thing about 208V is that a connection from of the three wires of the 208V service to the neutral provides 120V single phase service. Two such connections can supply a standard 240V dryer/etc. While the 120V single phase powers lights/etc. There are special commercial appliances available at extra cost that are designed for three phase but I doubt they were required here.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I have seen many thoughtful comments about codes and regulations, but have not responded because this does not seem like the proper forum for such a discussion. Can we start a new forum dedicated to preventing "engineering disasters", that deals strictly with inspection and repair of existing structures in terms of codes and regulations, so that we can actually help the general lay person?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
That's a pretty useless camera if it requires a large portion of a building to move before it records anything.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Yes, there is also that piece of bent rebar that could be from the slab. I can see 2 lines outlining what could be the top and bottom surfaces of the slab too. I'm not understanding why a rebar in a column ending in a slab joint would be an issue?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
As for the wild theories going around. The two didn't observe anything out of the ordinary. I would imagine that if the car-slammed-into-column theory had any credit (which I doubt, personally), they'd have perhaps noticed plastic, glass, metal, car liquids, tire signs – anything from the car, really – that would deviate from the ordinary, and it would have been right on their path. Or maybe they did notice, but given the magnitude of extraordinary things that happened afterwards, they just didn't recall these specific details in their telling... but again, it'd be a stretch, I could think of at least 5 different things more plausible than that. Secondly, I'd also rule out their own involvement (I think I saw a comment here implying that perhaps they could have been responsible instead), there would have been simply no time for them to hit a column, recollect themselves after the fact, and then carry on like nothing had happened - given they barely made it out as is. Those implying they fled shortly afterwards because they had something to hide, they were there only temporarily and weren't owners in the complex. I'd imagine the first thing I'd do, if I were in a city I'm only temporarily in and a building I had no particular relation with came down on me, would be getting back home asap. I'd also imagine, much like for any of the other survivors, that on top of what was made publicly known, officials have collected their statements privately. What we know and what they know might not necessarily have the same depth.
I've read the mulling on "when it was only structural people discussing it". With all due respect, much of what is being done here, at the time being, is speculation. Literally all of what is being done here is, including combing through "hard facts", i.e. schematics and plans. Witnesses accounts are notoriously unreliable, but pretending that looking at plans, photos and documents on the internet isn't is a bit delusional, too. For all we know, things were omitted from documents ("curious results" in the cores, yeah, thank you very much, I guess?), plans vs. how it was actually built differ, and photos and videos (more so if sub-potato quality) can be deceiving by their own very nature. Without being there and with the limited access we have (thankfully, I'd say), we know no better. If the scope of the exercise was strictly limited to discussing good/bad practices then by all means, I agree that having experts in those specific fields is the bee's knees, but over the span of 5 topics it simply unhinged from that premise and became a let's throw around hypotheses on the cause - including from structural engineers themselves - so the finger pointing now seems a bit uncalled for.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
And as for not believing that the other guy would leave that complex to check into a hotel, just because the power had been cut to the unit they were going to stay in, I suggest that you have never tried to sleep one single summer night in Miami with no AC, especially if you are used to cooler nights. Totally plausible. Ask for a night's refund the next day.
I also don't think that the camera was necessarily triggered by motion of the falling debris across the street, high up and in relative darkness, but by the seismic event of the first large pieces hitting the ground and swaying the camera, causing it to see relative motion of objects within the well lighted close field of view. I think I see some evidence of that in the ripple patterns in the pool as well. If the wind started the camera swaying, it would be recording all the time.
My guess would be 4000psi concrete in columns made in 1981.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
If both of these prove to be true, it gives actual evidence to the falling penthouse balcony theory.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
No visible damage to the column and no apparent damage to the car. The car was completely drive-able and you had to know where to look to see what visible damage existed. The plastic bumper cover popped back into shape. There was minor scuffing of a bright strip.
A few years later the car had to pass an extensive safety check and I had some expensive repairs of hidden damage to the rear underside.
Could a car have backed into a column with soft concrete and corroded rebar, seriously damaged the column, and still been drive-able?
I vote yes.
Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
On Floor 2, all three phases were distributed approximately equally, from a 3 phase 600A 208V sub-main breaker on that floor (this is where individual meters were). That is, 1/3 got phase A 208V, 1/3 got phase B 208V, and 1/3 got phase C 208V. Of course, the 120V went along for the ride.
For the remaining floors, the three phase was distributed as single phase over TWO floors, from a single location, in a similar manner. The sub-main was 800A.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
This is a recording of a recording being played on a monitor. It’s just as likely that that’s where they cued it up to in their haste to make splash with the media.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Pic is from Google Maps, it's actually on the north face of the building and it's most likely a cable. Navigating through the pictures from previous years, it's been there all along (I can't tell in the 2011 picture, but for sure from 2014 onwards).
Otoh if anyone wants to have a look at the joint between the wall enclosing the area accessible from the overhead and the penthouse roof on the actual collapse side, and if it may have been a weak point... I'm not sure anything can actually be inferred from the sorry state of the Google pictures (the only ones I've seen are from 2014/2015) and I'm not structural so it may just be the way it's supposed to be, but hopefully structural guys here can chime in?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Maybe we will just have to wait and see where that landed.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
You may wish to make a correction to avoid future confusion. Elena Blasser and her mother lived in PH 11. Link
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Video link above showing high rise movement after 7.9 after shock for visual explanation.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Interesting question, only because I have witnessed a kid in Miami on a job jump off the 6th floor thinking he could special forces swing into the floor below. He was instructed to drop to the floor below by his supervisor, so he did. Thankfully fall harnesses work, but the labor force in Miami is very suspect.
Could there have been a bag of roofing tools and/or rolls tied off to the new anchor points and hung off the side of the building?
Total speculation.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Perhaps I am being pedantic here but you need two phases and a neutral for each apartment to have 208/120v. Such as 1/3 get A phase, B phase and neutral, 1/3 get B phase, C phase and neutral and 1/3 get C phase, A phase and neutral.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Interesting question, only because I have witnessed a kid in Miami on a job jump off the 6th floor thinking he could special forces swing into the floor below. He was instructed to drop to the floor below by his supervisor, so he did. Thankfully fall harnesses work, but the labor force in Miami is very suspect.
Could there have been a bag of roofing tools and/or rolls tied off to the new anchor points and hung off the side of the building?]
Definitely Plausible with suspect work force..........So the green bundle of roll roofing could have been say the 2500 lb test rig, and tied to roof anchor with rope across top of parapet to really load those cantilevers well?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
To my tired eyes, that portion looks exactly like the view I believe we see from thr tiktok video, and why we do not see particular columns, beams, or fully discernable items from the location other than fallen rock looking structure, draining water pouring in from a similar flow path, and hanging debris.
*shrugs*
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Good catch, and there always is the possibility that the first collapse was a roof area above a condo with the green bundle sitting on top So the power flashes could have been an internal failure of roof slab we were seeing before the later events.
But it appears that bundle was sitting near if not on cantilever of 12th floor roof, and you can see where the flying buttress wall for the penthouse crashed down on the potential green bundle in that area
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Perhaps. But the power to each unit is called single phase.
Interestingly there has been two phase electricity, also. But since you need 4 wires to run two phase but only 3 wires to run 3 phase, I doubt it's in much use anywhere.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
But how these get triggered is by percentage of movement.. so they won't pick up palm trees, etc, swinging in the breeze. They're meant to pick up movement of a person in the foreground, so anything smaller than about that size is unlikely to get caught. It probably triggered at this moment because the movement was finally big enough to look like a person. It seems like the trigger probably missed a second of the movement as it turned on too, which is why we see the roof already collapsing down when it first starts.
Also, PH-11 and 1211 are the same apartment btw. And the roof theory seems sort of unlikely because of how far that collapsed column is from the roof area. Something would have had to have fallen from the roof, moved over a few feet on the way down so it fell right above a column, and somehow damaged it so much that it's not easy to see in the tiktok video.
I'm also curious about Demented's question earlier:
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
You can call it single phase if you want, but you need three wires to get dual voltages. American homes have dual voltages as well and have two phase wires and a center taped neutral. That's how it's done and it is the same with three phase systems.
Two phase power is still in very limited use, mostly for old elevator service in old buildings in cities like Philadelphia. My 1932 code book has a diagram that shows how to wire a two phase 5 wire transformer. ( see also Scott-t transformer connections for 3 phase to two phase 5 wire).
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Things don’t just stop in their cold tracks where they land. There is multi-axis vectors involved, and of course bounce and roll effects. Drop a ball off roof and I bet it does not end up in same spot as it first impacted the ground.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
There is 3 phase supply wiring to the building (Wye or delta) . No 2 phase in this building (Theoretically possible but surely not here in this century. You are right that 2 phase non-existant in USA today) Depending on internal wiring connection/ transformers supplies one phase loads in the building. Some three phase power distributions have 4 wires (neutral as well as three hot conductors). I worked for an electric utility. All loads in building condos likely 1 phase. Only large motors (3 to 5 hp and above would run directly on 3 phase power.
Lots of flxibility to the end user but in this size building the utility supplies a 3 phase service which can be made to supply single phase appliances.
Has little to do with the why the structure collapsed. Need a better video of collapse for starters. Otherwise will take months.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Several days ago someone posted a link to a YouTube video by an architecture professor (in Argentina?) that was very well done. He posted an updated video yesterday and I haven't seen it linked or discussed here yet so I thought I'd post the link:
https://youtu.be/c-1wwF_STiY
I don't speak Spanish but I turned on closed captioning and in the Options I chose to auto-generate captions in English. I was able to get the gist of what he was saying.
I'm not a structural engineer, rather I'm a Cybersecurity Engineer, but I'm finding the discussions here fascinating.
Cheers,
Tony
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Nothing to do with the collapse, but the electrical discussion started when people questioned how some lights were still on in the video when the building had already fallen 20 feet. The bluish colored lights are most likely arc flashes from the feeder wires getting pulled out.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
This guy?
Hired engineer: Still ‘no inkling’ to why Surfside building collapsed
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
My IP cam has a 0-100 sensitivity setting for the trigger.
You can also set how the triggered activity gets recorded. I can record up to 20 seconds *before* the detected movement (not yet flushed from camera memory by new data) if I set it as such.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Could the units be split-single phase, or would this require an extra transformer on each floor?
The main answer I’m trying to get to is how many different phases - that is, 120 degree phases off the 480 system - left the electrical room on each floor, and in what combinations.
Was each floor balanced across all three phases? Was each floor given 2 of the 3 and the system balanced across all floors but not each floor? Or did each floor have a split-phase 120/240 and only one of the 480 phases was active for each floor?
Because it looks like some of the floors go out at the same time, leading me to think they shared a phase. Ultimately, if we knew which phases fed which units, it may be possible to positively identify the floors by which other floors they were sharing a phase with, based on when the lights went out.
What got me started on this was the light in an x10 unit being turned on during the collapse. I was hoping to compare that to which of the x10s were occupied at the time. Unfortunately, all of the upper ones were, so it’s no help. But maybe the electrical outage sequence could lead to pairing up two sets of lights and confirming they are floors 9 and 11 for example, as opposed to 8 and 10.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Considering some of the other alarming things we have seen in the reinforcement steel, it is possible and maybe even likely that the pool slab was poured first and then the top half of the 'beam' and patio slabs were poured on top of the pool deck. This would pretty much eliminate any support along that edge. Also, although there are small beams along the K-M column lines, these are also stepped with the deck. Depending on how the steel was laid and how the slabs were poured, these beams may not provide much support.
My theory is that the pool level slab lost support midway between lines 9.1 and 11.1, probably right at the step-up. This overloaded M11.1 and L11.1 for certain, and probably also K11.1 to start. I am 90% certain that the stills from the garage entrance show that the planter that was on top of M11.1 punch sheared over the column and this caused the column to collapse. I think that the lower yellow part of the column is inside of the planter and the top part is broken and laying on top of the planter. The next bay to the north (M-N) does not have a patio level slab and appears clear of debris.
If, as I suspect, the failure was midspan, you would then have the patio slab hanging off the the 9.1 columns and likely attached with a few hook bars. While the moment load would be large, I don't think it would have been fatal. However, it is not hard to imagine the hook bars taking large chunks out of columns K, L, & M on the 9.1 line. The building might withstand one damaged column, but three in line on the outside line of the building would likely bring it down. Had everything been on the same level, the bars would have been continuous over the columns and this probably would not have been an issue.
There was also progressive failure of the slab from north to south, which from witness accounts probably happened before the 9.1 column line failure. However, none of this really mattered, once the slab failed between 9.1 and 11.1 the building was doomed. Similar column failures did not happen along column line I on the southeast side of the building because the slab was one level and dropped as a unit instead of being cantilevered and damaging the column as hook bars pulled out.
Potential Causes:
1) Design - While the design my have met all RCC codes at the time, the slab steps midway between column lines is less than ideal, especially with the planters added right on that step. Drainage for the exposed slabs appears to have been inadequate.
2) Modifications - It appears that planters were added over the years that may have made matters worse. These is a flat planter south of the original taller planters and the large square planters on line 11.1 appear to have been added as well. These contained palm trees for several years and added considerable weight.
3) Construction - Rebar placement does not appear to have been done according to plan and there are several disturbing pictures of atypical punch shear, evidence of very poor column/floor attachments, etc.
4) Maintenance - Allowing water infiltration for years was clearly an issue and needed to be dealt with more aggressively. It also appears that some of the work was not done properly and this all contributed. Not that one top bar was the difference, but I would not like to have to defend coring through it when methods exist for avoiding that issue.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
IF it is two bars terminating in a gap, the problem becomes one of column capacity, particularly after 40 years.
Columns suppor axial load, and both concrete and steel shorten under compressive loads. Initially they share loads according to their ED ADD relative area and elasticity. Add the creep of concrete when under continuous loads for long periods and the concrete begins to transfer some of that load to the steel, which does not creep. The transfer from bar to bar is usually thru bond and concrete shear between the bars.
The gap would not allow that transfer.
In the perceived case of a gap, at a slab connection, either bar would have no development length beyond the gap, and therefore no stress development to provide anchorage and resist moments induced at the joint. In short, if all bars were 'gapped' there would be no stabilizing effect at the joint and the column would likely loose capacity.
EDIT ADD When a bar in compression MUST be aligned above and below the splice, mechanical couplers are used to maintain the alignment and contact between the bars spliced. That maintains the loads and passes that load to the bar below. The couplers come in several forms - some are fitted and fused in place by igniting a powder to melt and lock in place, some are crimped in place just like a butt connector in an automotive wire, and some thread the bars using a steep taper and short coupler threaded together, similar to pipe.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
For example, are any of these objects visible?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It's very hard to make out though, so I'm not sure that's correct. But if that's the case.. we wouldn't be able to see any of those objects. Since we can't clearly see column 28/M12.1 it's hard to say though. I think that white object on the ground might just be one of their planters too, not the missing column.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I can understand that KCE wouldn't want to speculate at this point in the investigation but its not quite right to say that its too early to form a hypothesis. We have the original plans which are LOADED with red flags that strongly suggest the original design was flawed. A serious investigation of the failure begins, logically, with a careful analysis of the loads on the building and the structural capacity at each critical location based on the original design. You cannot assume that because the building stood for 40 years that the design was correct, whether or not it was done to code. If after this analysis, you don't find a flaw then you move on to other causal factors, including concrete and rebar deterioration, construction errors, additional loads added later, catastrophic loads immediately prior to the collapse, etc.
As far as this talk about various roof elements causing the collapse, I think most structural engineers, myself included, are not that interested in this discussion, maybe it triggered the collapse, or maybe not. What really concerns me is that Morabito inspected the building and did not really find anything that would make any engineer think that the building would collapse 3 years later. The worst damage he shows is to the pool area which stayed completely intact throughout the oollapse.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It should be an exact line, and from that, maybe some of the other details match (or don’t match). But the line can be drawn exactly if you have a few known points, which we do. Every object in the Tiktok video can be placed within a triangle in the pool deck, and for one dimensional objects like the vertical gate bars, you can draw exact zones across the pool deck.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
IMO, we only care about the trigger, in order to understand the design, construction, or maintenance issue it exploited, or in reality the combination of factors that led to the perfect storm. With this information, designers and code agencies can determine requirements that prevent tis tragedy from happening again. Collective brainstorming aids the process, but unfortunately it brings excess baggage too. If I am Alan, I want us to shut up on one hand, but on the other, I bet he has a groupie reading this forum.
Catch 22
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Questions that would serve to illuminate:
- Is there any rusting of the #3 bars at the slab drop beam?
- How far are the #5 hooked bars developed in the slabs at the transitions?
- Did they hook the "Beam A" bars into the columns?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Js5180, I think if the pool deck were still standing, it'd be about here.. it's hard to place within the rubble though since you can't see it. I'm not sure if it's a diagonal cut either, seems like it could be straight and just sloping down in the direction of the V during the video.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
But the PE SI had thoroughly inspected the facility, and was managing current phase of work. So it appears he saw no issues that would lead to this being an emergency. You can not see hidden problems with mostly a vision analysis.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Teguci, Nice write up! That white line I drew where the slab looks collapsed in that garage video is also suspiciously close to where you suspect the failure occurred. The rest of the slab nearest to the building seems to be on the floor of the garage, and M12.1 seems like it might be already puncture sheered. It all lines up really well with your thoughts on it too. It's nice to see the deterioration theory clearly written up.. although, very scary too.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Basically, tracing rays from the camera, through each bar in the gate, and out to the pool deck. We have exact blueprints and dozens of fixed objects to use. I may be able to work on it later, but this is the idea:
Then you can compare objects in each zone of the pool deck with objects in the tilt ok and try to determine if any of them match up. I’m thinking that white planter box is a candidate.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Why are you ignoring facts like the fully developed crack in the cantilever/parapet over the 12 th floor. I assume because we don’t need to worry about suspended slab problems, because you already know it was solely bottoms up?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Actually it might have been just over sliding door line?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Js5180, Nothing in that photo lines up because it's underneath all of the rubble. Perhaps I should have drawn the line on the ground so it was easier to visualize instead of where the slab used to be.. but it's under the rubble in that pic. The planter is next to and behind column 28/M12.1 and something is clearly blocking the view to it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Picture is opposite hand of area of interest. Perhaps, old eye-brain function. But theory still valid and remaining green tarp or bag is in right spot.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I'll try to answer your questions but I have not seen the electrical drawings and it seems that spsalso has so I will use the info he posted and my real world experience.
The building probably had 480/277 service for things like fire pump, domestic water pumps and pool equipment. 277v could have been used for house lighting. Then they would need a large transformer to provide 120/208v three phase. This would be fed to sub panels throughout the building. The sub panels each fed two floors of apartments above the 2nd floor. The 2nd floor panel MAY have fed a service panel for house lighting and general use receptacles for all floors so you can't use a sequence of lighting outages to help determine how the building failed.
Each sub panel would feed an equal number of units with a two pole breaker giving 120/208 "split phase". The phases are 120 degrees apart instead of 180 degrees and that is why it is 208v and not 240v. You lose efficiency for loads like water heaters and ovens but save on needing more transformers.
You can never balance the loads completely because some units on the same phase may be unoccupied. The best you can do is feed the same number of units on each phase and monitor usage to see if you need to re-balance later. With 24 units being fed from each panel you would feed 8 of them from a two pole breaker on A and B phase, 8 from B and C phase and 8 from C and A phase. That gives you 208v for each and then add a neutral for the 120v circuits.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Fire water supply piping should exit out of the generator room and do a vertical run. The dryer vents, not sure what path they take, where they are.
I just wonder if that's a roof-basement weakness or path. Some fire-proofing was going to be added at each floor and not sure if there is concrete there.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Most apartment panels in a 120/208V 3P4W system will have 2 hots and a neutral. These will get staggered in the meter bank, e.g. Meter 1 is L1L2+N, Meter 2 is L2L3+N, etc.
More importantly, though, is that the runouts (and sometimes the risers) from meter banks to apartment panels are very frequently run in flexible metallic conduit (FMC) in a drop ceiling, soffit, or other interstitial space. Unless someone can conclusively prove that all the apartment runouts were piped in EMT, you really can't, and shouldn't, read anything at all into the timing of the lights going out.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Yes. They exit the generator room and go through the parking level to the stairwells where they are protected and still accessible for testing and maintenance.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
NOT.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
He never looks at M10.1, but on the left you can see M11.1, and M12.1 at the center of the screen. There is no beam connecting M10.1 to M11.1 in their garage, and no step in between them. Instead the step seems to be sitting on M10.1. Or perhaps there's a soffit or a drop ceiling covering it there? If not, it does make you wonder if they noticed the flaw in between the two buildings and then tried to fix it on the north one.
I think the curious thing MC noted was that the building slab actually did have a slope to it when he tested it in 2020, but in 2018 that was his best guess for why it was so deteriorated within the garage. It's brought up a bit in those board meeting notes in 2020, and it says that he was going to need to test the slope further. It makes sense that the design problem was actually much more complicated than that.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
What evidence do you have for that? The electrical riser diagram (page 83 of the big PDF) has the entire building on 208V 3 phase, unless I'm missing something, so there shouldn't be any transformer other than the main one beside the service entrance. That part of the building survived the collapse without much damage. The subsequent fires in that area might have come from that transformer vault, possibly, but that's secondary to the major collapse.
It was between column lines C and D, and between row 1 and 2. That's the far west segment of the northern exterior wall. Nothing I have seen points to a transformer explosion there, or anywhere else. It's a long way away from K–M on the 9.1 row.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
You can also see a lot of deterioration on that planter above M11.1 (the one on the right in the pic) if you zoom into the pic.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It looks like all the electric wires come up from one place, then go horizontal through the even numbered floors. The plans have a meter room on some floors, and in pictures you can see what looks like 12 conduits coming from the shear wall where the meter room should be, on the even floors as the plans predict. So the x10s and x11s should have lost power as soon as the slab broke from the shear wall.
Page 58
Page 83
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
SF Charlie
Eng-Tips.com Forum Policies
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Sorry, I still think the Patio Table looks an awful like the ventilator from the garage roof
SF Charlie
Eng-Tips.com Forum Policies
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I give up, I am out. I can not keep facts straight when looking at pictures....
Old Age Sucks!
Please don't everybody clap at once.............
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
That's an excellent point. It's a level of detail on a small level that is known from other sources (not the frame from tictok rendering that I have seen). You can infer something from any attempt to enhance detail using that as a reference.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Here's a rough drawing of what I think the slab on the ground in the tiktok video looked like exactly, and where it was before the collapse if it fell straight down. It all seems to line up too well with what he suggested. I guess this means that missing column must be hiding from view under the planter.. makes the most sense really. I left out all of the areas that are outside of the camera view too.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I notice the closets are on 2-5-8-11, while the riser diagram shows 2-3-5-7-9-11, and I don’t see anything covering the PH. Not sure why they would be different.
Do you see anything that indicates different phases?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
You're just overloaded right now. To be expected. Take a well deserved deep breath and come back with a fresh perspective. Everyone's been there.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Regardless of that discrepancy, I think your hypothesis pretty much aligns with what I was thinking yesterday:
However, my thinking evolved after it came to light that the surface level parking area along Collins Ave may have collapsed virtually at the same time as the planter area around column M11.1:
So if we accept the timing of the surface parking collapse and we take into account the many punching shear failures that were the first thing everyone noticed when the dust settled, do you agree with the logic that the initial plaza slab collapse was more likely a much more widespread event? I believe that the failure of the planter area and beams connected to M10 eventually triggered the building collapse, but I'm not so sure anymore that the plaza slab failure started there. It seems to me more likely that it was a widespread progressive collapse of the entire plaza slab, that may have slowly accelerated over several hours based on the timing of witness accounts of creaking/cracking noises. Putting the timing of the tik tok video together with the timing of the Vazquez/Accardi elevator ride, it would appear the planter area and surface parking area collapsed about at the same time. Since those two areas are on opposing sides of the lobby, it follows that the plaza slab collapse was widespread and wrapped around the building. This is consistent with the aerial images that show the slab sheared around the perimeter of the basement. Initially it was hard to say whether this was a precursor or a symptom of the building crashing down onto the slab, but I'm leaning towards the precursor theory.
Does this logic make sense?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I don't know the current break point but guess around 400 Amps plus for the service to go three phase.
The breakers are installed onto bus bar extensions.
From top to bottom in a panel the bus bar extension phasing is:
A phase.
B Phase.
C Phase.
A phase.
B Phase.
C Phase.
A phase.
B Phase.
C Phase.
repeat.
The top breakers are A + B phase.
The next breakers are C + A phase.
The next breaker spots are B + C phase.
In Canada AC90 is often used for feeders to apartments. Armoured Cable, 90 degrees Celsius rated.
The labour cost is often the lowest.
480/277 Volts for large motors? Again an economic concern.
First choice is all 120/208 Volts.
If the addition of the large motor loads in the design phase requires a larger transformer, then the option of a larger transformer may be compared with the option of a second 480/277 volt transformer.
Another factor may be the use of motors above 200 HP.
A rule of thumb says that it is desirable that the motor HP not exceed the voltage.
The rule may be broken on both economic grounds and on voltage dip when a large motor starts.
It depends.
Most designers will run one 250 HP motor on a large 120/208 Volt service.
A 400 HP chiller motor will have serious consideration of a higher voltage.
Four wire, 120/240 Volt delta? Forget it. Too many problems for large single phase loads.
Such as: the transformer bank capacity is reduced by 1/3.
For a given single phase 100 KVA load:
One phase will have 50 KVA at unity power factor.
One phase will have 50 KVA at 50% lagging power factor.
One phase will have 50 KVA at 50% leading power factor.
Wait! That's a total of 150 KVA for a 100 KVA load.
That is correct.
I told you that the four wire delta connection was problematic for large single phase loads.
Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Page 9 of the original structural report lays it all out for us.
Florida rainy season just started. 2.88" of rain in an area in 3 days collecting on a 0 years left slab. Unfortunate. Some simple shoring probably could have prevented this, but alas, that would have blocked the parking entrance and they needed the towns permission for off-site parking.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
It doesn't take a rocket surgeon to put 2 and 2 together, or does it?
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Is it just me or does it look like a roof anchor crashed through the wall in this picture?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
For what is is worth to anybody, these are the images I have been referencing/processing during my reading:
Entryway Frame 259 Raw:
Entryway Frame 259 Deep:
Entryway Frame 274 Raw:
Entryway Frame 274 Deep:
Entryway Frame 291 Raw:
Entryway Frame 291 Deep:
and maybe I'm blind, but I'm not seeing anything that might resemble objects "from the roof". Rolls of tar paper etc...
EDIT: "hi-res" links:
1: Entryway Frame 259 Raw
2: Entryway Frame 259 Deep
3: Entryway Frame 274 Raw
4: Entryway Frame 274 Deep
5: Entryway Frame 291 Raw
6: Entryway Frame 291 Deep
Thanks.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
You might even decide to gather your valuables and go sleep in a hotel...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Link
Notice how specific they were about the concrete drilling and refilling... Wonder why they are being so detailed specifically on this in the article?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
"STI’s technical consultant and presenter of the webinar, Mustafa Mahamid, PhD, PE, is currently on site at the Champlain Towers South building collapse in Florida. He is assisting in the evaluation and recovery efforts there, and this effort will take him beyond July 14th. Our hearts go out to all those who lost their lives or loved ones in this disaster and to all the volunteers who are continuing to work in difficult conditions.
We appreciate your patience as we work to find a new date for the webinar. You will be notified as soon as possible of the rescheduled date. If the new date does not work for your schedule, we will offer a refund. If you have questions, please email us at hssinfo@steeltubeinstitute.org."
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 05
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 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
How long will the garage ceiling or visitor parking deck stay in place after a column is removed, by a car or other event? Please provide your answer in 'seconds'.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Edit: nvm. I see it now.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
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 05
Excellent information is this post even though we learned this building was only 208/120, however the third breaker in your example would be B + C phase, then it repeats.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I found this in a YouTube comment. Is this true? If so, it is sickening.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
No one posted "where exactly Eric Zion lived in NYC". The point was just that he may have been driving in from NYC. We don't know that yet, but maybe someone will find out where he was coming from. No one is advocating stalking and harassing this person. BUT, I know that investigators, and perhaps even police detectives, sometimes read this forum for ideas on what is possible. So stating an idea for investigation here means that someone might look into it.
It's also a difference in interest. I think it's good for all disciplines to participate. Many from mechanical and IT have helped explain what would be expected with a building of this vintage, etc.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Eyewitness from room 111 reported that there was enough time between a loud crash and the observation of the plaza slab failing and then enough time from the plaza collapse to the building collapse for her family to escape. Punching shear is usually instantaneous, so the load crash would seem to be from an earlier trigger event. Further, I haven't been able to find an explanation why punching shear would occur at night without some other preceding event. Do you have any ideas for other triggering events? I do believe that the plaza failure, once initiated, happened like a quick wave radiating from the planter failure.
I think the final building failure occurred at K/10 when the weight of the failed plaza slab was applied to the "beam A" which then applied moment to the building column. Not entirely sure why there was a pause , but I'm glad the family from 111 was able to escape due to it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Pretty sure with a cracking overweighted slab, we'd here banging and popping noises similar to construction noises as the slab cracks, stretches, and shears the rebar.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I've spent many post-hurricane nights on the Gulf Coast in a house without power. We have never gone to a hotel.
His mother owned condo, so there would not be "a nigtht's refund".
What is suspicious about the sudden hotel stay is the following:
He stated that he had just returned from a trip/travel with his wife. What did he need? Presumably he had his toothbrush and could hand-wash his skivvies if they all needed laundering. He spent a lot of time (1 hour) trying to get the power on (or was he gathering valuables?) and more time (30-40 minutes) getting other necessities after midnight. Most people would rather be showering and getting some rest in the hotel that they paid for.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I think that security camera has that view to get a view of the pool area, in case of excessive people in the pool (an unauthorized party) or in the case of a drowning. Maybe someone with knowledge of condo security cameras will have more info.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Aren't those Electricals so cute with their talk of phases, breakers, and neutrals?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
That sounds feasible. In my limited experience with CCTV, you can use a mask to exclude the areas where you don’t want movement to trigger the camera.
Notice that bush waving around in the foreground to the left. If this was a motion trigger, the bush would have likely triggered it. If it was a mask and it was activity in the pool they wanted as a trigger, they would have masked everything but the pool.
It’s weird to me that the footage faded in from the “no video” screen. Go frame by frame from the beginning to see it. If it were a constrained clip of some sort, starting with a trigger, wouldn’t it start with a static screen and a play button, or after being selected from a catalog of clips?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
NOLAscience, I'm sorry, but your insistence that this is a good place to investigate victims is the main reason I'm leaving this thread. It's sick.. let them have their privacy. I'm sure the cops are going to ignore every single one of your posts about Eric because they're all so misguided. And saying we need more information on where they were parked so we understand their statements is totally incorrect, we know that no one could have entered the garage without seeing the rubble pile. Digging for that info is just a gross attempt to place blame on someone more specific, to gain some traction to these insane theories that someone maliciously killed over 100 people and then waltzed off to a hotel for the night. And if you manage to get a specific person into a few lay people's heads that are reading these threads.. they can run away with the info and get crazy with it. It's happened time and time again with internet "web sleuthing."
I want no part at all in a forum that thinks it's okay to witch hunt any of these people. I honestly thought this was a group of professionals that wanted to discuss the building, but clearly some of you are not. I'm out.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
a capacity of 320 TONS. Impressive.
https://youtu.be/c-1wwF_STiY
EDIT TO ADD: This is a FANTASTIC video, and well worth the 30 minutes. It is so fast-paced; after the intro, the video is packed with information with technical ideas presented in a way that almost anyone can understand. He uses a very nice 3D model and even some cardboard mock-ups of different structural systems.
I think he has an error in his calculation of live load, which he calls "overload". 40 psf is 200 kilos/sq meter and he says (or the translation says) 300 ksm. Also, I don't see that he used any live load reduction, discussed on Thread 1 or Thread 2 of this forum discussion.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Back at you:
Aren't some of those those Structurals so cute with their mangled understanding of phases, breakers, and neutrals?
Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
One thing you can see looking through the original plans is that the designer changed the foundation design from closely spaced precast concrete piles (PC) with a capacity of 50 tons each to a pressure injected footing (PIF) with a theoretical capacity of 150 tons each. This was clearly done to reduce cost as it allowed 2/3 of the piles to be removed. The revised layout with significantly greater spacing is shown in the drawings but the change doesn’t appear to have been incorporated correctly into the foundation design as there are some missing details.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Perhaps there is a foundation issue? You have water seeping into the foundation in this region. This region is the region that failed the building. This spot seems to be where the trigger and cause will be found right?
If it's roof slab failure, then the roof hitting the pool deck just above here is the trigger, but foundation issues could also be an issue. Soil underneath this area could be a problem. How can you get such a crack on a foundation slab? Surely that thing is thick as and is resting on the pilings right?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
They are actually providing some good information to correct some misinformation that's been given. Although I'm not sure exactly what difference the electrical discussion makes because it certainly wasn't the cause of the collapse.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Regardless of where else there was instability, collapsed slab, etc., a roof collapse of any kind could easily be the final trigger. That’s why I see the electrical discussion as relevant.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
One wonders why you are so touchy about this. I am not alone in saying that Zion's story doesn't ring true. This does not mean that it is NOT true; it just means that there is much about it that should be investigated.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
And so he decided to swipe at that very Electrical, ever so gently.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I'm having trouble seeing that within the context of the whole.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Please allow me to move the discussion to:
Miami Beach, Champlain Towers South apartment building collapse, Part 06
Thank-you.
Someone Please close this post to new postings, or message me how to do this, Thanks.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
I think it would be easier to calculate the energy transferred into to the car.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Click on Report at the lower right hand side of a post.
Send a message something like this:
Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
Not at all. I was just trying to make a little joke because the Electricals were having a side convo that kept coming up and coming up, and no one else was interacting with it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 05
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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