Miami Beach, Champlain Towers South apartment building collapse, Part 12
Miami Beach, Champlain Towers South apartment building collapse, Part 12
(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, Part 05
Miami Beach, Champlain Towers South apartment building collapse, Part 06
Miami Beach, Champlain Towers South apartment building collapse, Part 07
Miami Beach, Champlain Towers South apartment building collapse, Part 08
Miami Beach, Champlain Towers South apartment building collapse, Part 09
Miami Beach, Champlain Towers South apartment building collapse, Part 10
Miami Beach, Champlain Towers South apartment building collapse, Part 11
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, Part 05
Miami Beach, Champlain Towers South apartment building collapse, Part 06
Miami Beach, Champlain Towers South apartment building collapse, Part 07
Miami Beach, Champlain Towers South apartment building collapse, Part 08
Miami Beach, Champlain Towers South apartment building collapse, Part 09
Miami Beach, Champlain Towers South apartment building collapse, Part 10
Miami Beach, Champlain Towers South apartment building collapse, Part 11
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The Long Winter Awaits
As the leaves of late summer wither ever so slightly, their mottled discolorations foretell their future. Soon, with the waning of daylight, their photosynthetic journey will halt, and gravity will return their mineral elements to the soil below.
Huddled amongst these trees have assembled the technological elite, intellectually curious, and professionally trained people of this land. Their ranks infiltrated as they are with charlatans, quacks, and poseurs; all stare in awe at the mighty forest that surrounds them.
The sun dappling their faces as each one takes in the light. “I know the reason the light shines!” says one. “I, too, know” says another, “but the light, it shines differently for me; reflected as if cast upon a scattering of invisible orbs.”
A third mills about, claiming there is not light at all. “Behold the mighty PowerPoint and gaze upon its infinite wisdom! It showeth thus the absence of light entirely! This pixel here! And that smudge outlined in chartreuse!”
What a tremendous cacophony all these voices make. It reverberates through the trunks like a flock of magpies what have been into the fermented crabapples.
But the light is growing ever dimmer. The playing of the shadows waning as the stomata gasp their final breaths. Darkness. Coldness.
The bleak monotony of winter marches ever closer. These ravenous minds yearn for a brightening sky to inform their views but none awaits. Only a monochrome landscape, stretching from woodland floor to the low gray stratus that hug the ground.
Unlimited shades of gray.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
In addition to the woman’s voice in the basement, which may refer to the teenage girl from 204, there are suppositions about victims from 704 and 1002, and descriptions of injuries to victims from these units:
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
From the article:
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
What a damning article on the whole process of design construction and permitting in this region of the country. The only thing I would say, from my experience, is that I don’t think things have changed all that much. It’s not unusual to see Cities, counties, and the State get intimidated into accepting substandard projects by developers and their lawyers.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
It says that Surfside had only a part-time building inspector and "delegated inspections of the towers back to the Champlain Towers builders...".
I may be overly naive here, but it seems to me that Surfside should have hired an additional Special Building Inspector, then. And assign that person to this job. The whole point of allowing this building was to bring in money to Surfside (according to the article). So it would seem appropriate to "spend a little to get a lot".
Besides, wouldn't the permit fees cover the cost of the inspection? That IS the point of permit fees, is it not?
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
"USA Today has had someone review the medical records. Apparently few autopsies were performed for religious reasons. At least 9 victims of 98 dead may have initially survived Surfside condo collapse, but were not found by rescue teams, investigation shows"
Thanks for the article. I find it highly disturbing on so any levels.
"Fire rescue logs indicate that officials knew hours after the 1:25 a.m. collapse at Champlain Towers South on June 24 that survivors remained in the mountain of debris. Rescue teams were in contact with live victims, and search dogs – one of the department’s most reliable indicators of life – confirmed human life."
You'd think as a "crime scene" autopsies would be mandated.. but suddenly "it was never a crime scene" but a death investigation??
Seems the County decided to pick and choose which records to keep or dispose of as well.
So much incompetence and subterfuge at the same time!
And once again the couple in 811..that were found holding their IDs...no visible injuries that would lead to death.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Miami: A search and rescue diary:
https://www.israelhayom.com/2021/08/06/miami-a-sea...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
From the article:
Another person who did not appear to have immediate life-threatening injuries was Gloria Machado, 71, who lived in Unit 1111.
Records show Machado suffered “fractures of the skull and facial bones, ribs, spinal column, legs, and feet,” as well as “global laceration of the scalp with multiple skull fractures and multiple facial fractures.”
Six minutes after the collapse, however, 911 operators received a call from a man claiming to be Machado’s son, fire rescue logs show.
The caller said he “received a call from his mother” and she was “trapped inside her apartment 1111 and unable to get out,” logs show.
Quite honestly, those injuries might not have immediately killed her, but they seem inconsistent with someone being awake/alert enough to make a call. Also, she said she was trapped in her apartment, not that not that it had collapsed.
There was some speculation a few threads back that before the actual collapse, the structure may have sagged and twisted such that doors could not be opened. I wonder if the call was made before the building fell?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Obviously I did not see your call to move to a new location.
Thanks,]
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
What they did, and why it took exceedingly long, so exceedingly long.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I would edit it - copy the text form the edit page (where you can change it) - and paste into a post on this page.
Sorry for mansplaining it...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The proper casting of a concrete member - beam, column, slab, footing, or wall is monolithic - one casting with reconsolidation between the layers of placement - or through a properly prepared cold joint.
Had I caught a contractor leaving an as placed joint surface in concrete he would have been sandblasting the entire surface to remove the interface surface sufficient to expose aggregates solidly embedded in the prior pour. That is a bit expensive.
On one project the contractor did not place the temperature reinforcing in a topping slab which was placed over precast tees. The flanges of the tees had been intentionally roughened just like DOT girders and were correctly prepared for a topping slab placement. The contractor should have called for an inspection. The remaining pile of reinforcing was the clue. He was directed to place the reinforcing, clean the slab, and coat the surface with epoxy. The reinforcing was temperature reinforcing - not the principal reinforcing providing strength for floor support, as the reinforcing of slabs at CTS was.
Cold joints were a problem at FIU. What is with the Florida contractors?
The concrete is/was likely mixed in a batching plant and trucked to the site. It might have been pumped or perhaps hoisted in buckets to the elevation being placed if there were a crane on the site. The handling of concrete, even in the 1980s, was clearly defined in the codes and industry practice. Batch times, number of turns of the drum on the truck, slump, added water - all are supposed to be controlled. Mixes are and were designed and load tags provided with reference to specific approved mixes, and the concrete sampled for slump and compressive strength. And it remains a problem today.
Reinforced concrete is the most structurally important product in most structures that is actually created on the job. Under less than factory controlled conditions - like rain, temperature, and other factors. But on the job it becomes just hard work, with a deadline only an hour away if you want to finish it correctly.
And yes - that is basically delamination by default.
Thanks,
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Yes that seems likely, in the x11 stack at least. That is probably why 811 couldn't escape, even though they were awake and aware enough to get their IDs and choose their death pose (that was the speculation in the previous thread). The timestamp on the call that the woman in 1111 made to her son would be extremely interesting.
It all lines up, to me, with something failing low down in one of the x11 column stacks (L or M 9.1 probably), leading to load distribution (with noises and deformation) for some minutes until the connection with that M9.1-11.1 beam breaks, the pool deck becomes unsupported and starts puncture-shearing the deck columns.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
NIST Establishes Expert Team to Investigate the Champlain Towers South Collapse
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
And yet, 611 (and the ground floor tenants) were the only ones that got out. Might the upper floors have actually deformed before/more so than the lower floors? Would the twisting (for want of a better word) have gotten worse as you went higher, despite the initial failure being at the base?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I just want to second what Vance is saying. I find it quite unbelievable that this practice may be occurring in Florida. In my opinion, ANY STRUCTURAL SLAB THAT HAS A HORIZONTAL CONSTRUCTION JOINT WITHIN ITS DEPTH IS SUSPECT. I'm not saying this is never done. But if required special care is demanded, and would usually be specifically detailed on the drawings to ensure it's properly done. It should never just be left to the contractor to install these at their whim.
Separately, the broken MC core samples, w/ loose rebar, are likely NOT the result of horizontal CJ's. They are much more likely the result of corroded rebar causing spalling within the concrete.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Ring video is picking up micro-level twisting and wracking going on in the structure pre-collapse. This would not be visible in the macro-level surveillance video. At least that's my take.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
These were on the drawing as not structurally integral, but in a packet of errors, what's to say these walls were not giving some support to the slabs.
The doors would be located between both sets of these walls.
Edit: Another thing to note is, this building had pretty much 100% coverage with hurricane rated glass.
Having just got off a job where we were literally hammering stainless steel on top of glass (and welding it too, oh the joys of 90* max inter-pass temp. FML), a little twist in a building that'll stop a door from opening wont even make that glass wince. The crappy aluminum or stainless frames around the glass have enough crush space that they'd give way about 2-3" before the glass even touches something hard. That glass wouldn't have broken until it was crushed. Layers upon layers of latex paint too. Even at higher quality, that side of the building probably wouldn't have shown us much.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Everything is speculation, of course.
But if you go to 34:36 in the 911 calls, there’s a call starting at 1:29:57, seven minutes after the collapse. They’ve edited out the unit number, but it’s likely to be the son of Gloria Machado in 1111. He says his mother told him “there was an explosion in her building” and “She’s trapped in her apartment.”
Given the timing of the call and the verbiage, I think you can make the argument that Ms. Machado survived the collapse, made the call, and then expired before rescue. Ms. Machado thought there had been an explosion in the building. She would have had no idea that the building itself had collapsed. All she could have known is that she was trapped in the rubble of her ruined apartment. What I’m trying to say is that the wracking of her door frame was unlikely to have been the reason she couldn’t get out, especially considering the extent of her injuries.
As for 811, we will never know why they grabbed their IDs and died in each other’s arms. Rather than being stuck in their apartment as a result of wracking, though, perhaps like the Nirs in 111 they believed they were experiencing an earthquake. When you’re in a high rise in an earthquake, you’re supposed to stay away from glass and wait it out, and then, after the shaking stops, put on your shoes, grab your purse, and evacuate. Maybe that’s what the people in 811 were preparing to do, having no way to anticipate a building collapse.
We know from what the Gonzalezes, who miraculously survived after plunging down from 904, said that the building was shaking violently on their level, so it would be natural to think it was an earthquake. The Gonzalezes’ decision to try to escape saved them…they got lucky. Like Ileana Monteagudo had done several minutes earlier in 611, the Gonzalezes in 904 got their apartment door open and ran out into the hallway.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
There was a guy on the officer's body cam saying that his mother was stuck in her apartment. The impression I had was that she was in the still standing part of the building? He might have been the one who called 911?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I would have also expected that she would have been described to dispatch as seriously injured and in need of immediate medical attention instead of trapped. And probably would have called 911 first herself.
Which makes me think the call was placed before the whole thing came down but after some shaking and wracking of the building took place.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The guy in the street trying to get the cops to save his mom seemed to be indicating the part still standing. I can’t decipher whether he says the apartment number. Go to 6:37 in this bodycam video and see if you can hear a unit number. He is talking to the cops at 1:36:35, which is 7 minutes after the 911 call about the mom trapped in her apartment and 14 minutes after the building collapsed.
Blue Shirt Fire Admin from 1209 described hearing something falling in the apartment and then described the sound of the building collapse as a jet. It’s questionable whether 1209 even heard the deck collapse. Ileana Monteagudo in 611 described the deck collapse as a supernatural force that woke her up. Because of these statements, I am having a hard time imagining someone in 1111 describing the deck collapse as an explosion. But assuming one person’s supernatural force is another person’s explosion, let’s imagine that Gloria Machado called her son immediately after the 1:15 deck collapse. It doesn’t make sense to me that her son would then wait until 1:29:57, nearly 15 minutes after the deck collapse and 7 minutes after the building collapse, to call 911 to report that his mother’s building had had an explosion and she was trapped in her apartment.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
It's still standing.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Let’s imagine, that she, like my mom who is of the same vintage, takes a few moments to get her bearings at 1:15 in the morning. And instead she called moments before the building collapsed after waking up, wandering about a bit, finding she can’t open the door, Gondi go her phone, and calling. That’s the better part of 5 minutes right there.
Where was here son calling from? If it was anywhere other than the immediate area he would have had to work a bit to get patched into the Miami-Dade County dispatch, no?
What did the building experience between the time Monteagudo was woken up by “strange noises” and the time after cracks started running in the wall, but while she ran about collecting credit cards, ID, various religious tokens, and then ran down several flights of stairs before the collapse happened. I can’t imagine that everything was serene.
Like you said, it’s all speculation. None of it will be resolved with any certainty. And even if it is, it sheds no relevant light on anything. We’ve had some 4,000 posts of that. Maybe it’s fodder for the lawyers. But other than that…
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Here’s the archived version of the Miami-Herald piece about it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
There was internal damage in portions of the standing portion. Surely there must have been rooms where people may have been stuck by doors that wouldn't open?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
"None of it will be resolved with any certainty. And even if it is, it sheds no relevant light on anything. We’ve had some 4,000 posts of that. Maybe it’s fodder for the lawyers. But other than that…"
Both NIST and Lawyers will re-interview all of these survivors/witnesses. It won't be "fodder" because they will ask better, more deliberate questions and have bilingual interviewers. Unlike journalists looking for a sensational soundbite.
Yes, we on here are at an extreme disadvantage trying to reinterpret any of the previous interviews.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Fire fighters did go completely thru the standing portion of the building that morning.
You can see at the very top, that is one of them with a flashlight.
Also, I was able to tie all of the deaths to the Units of the collapsed portion, I kept a spreadsheet. I started it because I knew the original number of 149 was incorrect. Cava knew the missing was under 100 within 2-3 days and never corrected herself... I wonder if this lie was upheld to help increase the state of emergency or fema funding?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
There is also a faint glow of flashlights on the stairwell landings.
What I am interested in is that vertical row of red lights. Are those exit signs with batteries at the end of the halls? (I'll start looking)
Found it...
That looks like what I'm seeing.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Edit: Ignore the marks and comments, as I just grabbed this from the lead in image to another long winded read and think out loud video for profit, which is just a bunch of hot air.......
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Now who's resorting to power-pointy do-dads
I recommend The Importance of Punching Shear at the Surfside Collapse starting at 9:55
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The concrete for that particular core sample does look particularly degraded (powdery). And at least from this view the steel looks relatively clean. It is still odd that the separation is occurring at the steel. Core samples don't normally break up. I'm not a materials expert, so I'll keep an open mind on causation until some actual testing is done.
Here is an image of that core from earlier in the thread Part 7, 18 Jul 21 1:10.
By the way, could anyone provide the link to the Morabito Phase IIA report where these come from. I can no longer find it. Is it within the Surfside document trove?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I don't have the literary skills of some of posters, so I had to join "Team" do-dads, to get my points across!
I looked in Surfside document trove and could not find it either. I thought that is where it was originally found, as it was buried in the 80 page Association Meeting Minutes.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
There have been comments on rainwater possibly causing weakening or dissolving rock strata below the building.
Now the question - about aggregates in Miami. Are the aggregates sensitive to degradation by salt water exposure? In the FIU photos of broken concrete almost all the aggregates I saw were split by the fracture. Good bond, not so good aggregates? Can we see aggregates in the crumbles here?
A comment on "congestive rebaritis" - I do not see anything out of the ordinary by viewing the pics of the columns - and if rebar is tight there is a max aggregate size to be used. At column bar splices, it is common practice to offset the bars from below to do a contact lap just above the floor slab pour , in this case. There is a detail of such a condition and it appears correct to me - bars offset at 1:6 slope and the offset should be offset toward the center of the column (I do not recall seeing the direction to orient the offset as a requirement on the drawings, but it is the practice). Reinforcing needs to be separated enough to allow good bond and load transfer between the concrete and reinforcing, and the codes address this. Mix properties as placed and proper consolidation of the concrete is required. Measurements will confirm compliance or non-compliance.
I am not sure the rebar spacing was a major contributor to the collapse. One column on line "L" is 24X12 and has 12 - #12 bars for about 5.3% steel, with the maximum allowed being 8%. Column on Line G , 14X18 and 10 - #11 is 6.07%, less than the 8% maximum.
Thanks,
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Unless things have changed... at the splice you can have 4% (main steel)... 4%+4% spiced bars = 8%.
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 12
That pic above that SFCharlie posted looks odd to me. In it there are 4 bars all in line and basically touching each other at the corner. Bundling of bars in EQ zones is done all the time. Usually the shape is triangular w/ 3 bars per group. Here, with them all in line, it seems like concrete placement could be a problem.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Link for - Phase IIA, Summary of Work Performed
https://s3.documentcloud.org/documents/20985354/20...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thanks Optical98!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Too much.
Too little
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The longitudinal reinforcing up the column is the determining factor and the focus of the 8% limitation.
If there are moments at the top of the slab/bottom of the column, the development length for any bar in tension should be checked.
BIGTIME EDIT - - I do not see the logic in this but is correct - the limit of 8% DOES apply to splice zones in the ACI318- 2014 Section 10, as follows (with comments). What this does today is require splice collars so all reinforcing stays in line and reduces the congestion if more than 4% is needed
From http://aghababaie.usc.ac.ir/files/1506505203365.pd...
10.6.1.1 For nonprestressed columns and for prestressed
columns with average fpe < 225 psi, area of longitudinal
reinforcement shall be at least 0.01Ag but shall not exceed
0.08Ag.
Discussion/Comments
R10.6.1.1 Limits are provided for both the minimum and
maximum longitudinal reinforcement ratios.
Maximum reinforcement—The amount of longitudinal
reinforcement is limited to ensure that concrete can be
effectively consolidated around the bars and to ensure that
columns designed according to the Code are similar to the
test specimens by which the Code was calibrated. The 0.08
limit applies at all sections, including splice regions, and
can also be considered a practical maximum for longitudinal reinforcement in terms of economy and requirements
for placing. Longitudinal reinforcement in columns should
usually not exceed 4 percent if the column bars are required
to be lap spliced, as the lap splice zone will have twice as
much reinforcement if all lap splices occur at the same
location.
I learned something toeday. Thank you,
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Partial depth repairs were done from above and below in the same locations, mostly around the planter locations. They went 3-6" down, and 3-6" up in their excavation to expose the rebar.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
An ACI Standard
Building Code Requirements for Structural Concrete
(ACI 318M-14) and Commentary (ACI 318RM-14)
Reported by ACI Committee 318
Chapter 10 Columns, page 156
I don't know if this is latest or correct source, so I attached document to this post.
R10.6—Reinforcement limits
R10.6.1 Minimum and maximum longitudinal reinforcement
R10.6.1.1 Limits are provided for both the minimum and maximum longitudinal reinforcement ratios.
Maximum reinforcement—The amount of longitudinal reinforcement is limited to ensure that concrete can be effectively consolidated around the bars and to ensure that columns designed according to the Code are similar to the test specimens by which the Code was calibrated. The 0.08 limit applies at all sections, including splice regions, and can also be considered a practical maximum for longitu- dinal reinforcement in terms of economy and requirements for placing. Longitudinal reinforcement in columns should usually not exceed 4 percent if the column bars are required to be lap spliced, as the lap splice zone will have twice as much reinforcement if all lap splices occur at the same location.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Does it apply at the base of the columns in the garage as well? I wouldn't have thought there would be any splicing there, as there isn't a column beneath that slab, and it didn't look like it in the pictures where they'd cleared the rubble but the columns were still present. And we know that, apart from maybe M12.1, all those columns were still standing at basement level.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The 4% limit was hiding in the back of my mind, and I was surprised when I saw the 8% - really! But there it was in bold - but without the comments.
The takeaway is a good thing - increase the size of the column if you need to exceed 4% reinforcing OR use splice couplers.
Now to find a copy of ACI318 that was in effect in 1980.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Not a problem... one of the features of this website. I haven't done a real concrete tower for two decades, but at that time the general maximum practical reinforcing ratio was about 2.5% to 3% (and max reinf at splices was about 6%) with column sizes and concrete strength only changing as needed to accommodate greater loads.
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 12
The condition of lapped reinforcing generally applies to the top of foundations also because it is difficult to set and hold a large tall cage of reinforcing over a deep pile cap or footing and while placing concrete. The dowels can be tied to mat reinforcing and most of the time no bracing is required.. But there are a lot of times the dowel bars are not straight vertical and in the right place.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Millennium Tower sank another inch this past month.
Underpinning to bedrock.
shoulda in the first place.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Perhaps SFCharlie can come up with a 'do-dad' fix? EDIT: Perhaps a series of Flying Buttresses like the old Cathedral's?
Next Question: Who wants to live in a High Rise on either Coast?
Link to NBC Bay Area article:
https://www.nbcbayarea.com/investigations/millenni...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
(that will take a while, but I'll get on it)
SFCharlie for one
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Its under SF Tower Settlement Part II - Key word here is "yet" but engineers are working on making it worse as we speak. Unbelievable!!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
but as you observe it looks barely harder than the cement, and is pale coloured presumably limestone.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
https://www.nbcbayarea.com/investigations/new-tilt...
as far as aggregates go... if there are chlorides in it, it can reduce the passivity of the concrete (not cement, that's the pozzolan used to make concrete) and reduce the ability to resist corrosion.
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 12
There, that wasn't so hard...
Now back to the aggregate
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Pound a whole buncha pilings in, all the way to bedrock.
IF the building tilts too much during the first phase, bungee cords are used as safety devices, and are tied around that cucumber shaped building nearby.
Phase two involves a whole lot of hydraulic jacks. One is placed above each pile, and the jacks lift the building back up to vertical. There will be a guy (paid double time, by the way) up on top with a 24" level. He will be in constant communication with management.
Phase two point one is removal of the bungee cords. Great care will be taken to avoid them "snapping" out a window or three on adjacent buildings.
Phase three is filling the whole cavity where the hydraulic jacks are with, yes, CONCRETE.
Phase four is the after-party, which will take place in the East Bay. Just in case.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Back to the aggregate in Miami (I know the group trying to build the new Panama Canal locks ran into a problem. They were going to use the rock quarried out of the lock site, but there was an unrecognized fault running through it and the rock was too fractured to meet spec, so they had to find a new quarry...)
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Saltwater corrosion of the aggregate or just "we don't need no stinkin' aggregate"
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
CTS is not the first one in Florida - -
While searching for a copy of ACI 318-77 I found this:
Source: https://www.concrete.org/publications/internationa...
Title: Cause of the Condominium Collapse in Cocoa Beach, Florida
Author(s): H. S. Lew, N. J. Carino and S. G. Fattal
Publication: Concrete International
Volume: 4
Issue: 8
Appears on pages(s): 64-73
Keywords: buildings; concrete construction; failure; flat concrete plates; punching shear; shear strength; strength; structural analysis.
Date: 8/1/1982
Abstract:
Gives the results of an investigation into the collapse of a five-story, flat-plate condominium building in Cocoa Beach, Fla. The collapse occurred on March 27, 1981, while the casting of the roof slab was in progress. Eleven workers were killed and 23 were injured. The investigators conducted on-site inspections, made laboratory tests, and made analytical studies. It was concluded that the most probable cause of the collapse was inadequate punching shear capacity in the fifth-floor slab to resist imposed construction loads. The analysis indicated that punching shear stresses at many slab/column connections were close to the ultimate capacity specified by the Code (ACI 318-77). Consequently, it was Concluded that a punching shear failure at a heavily stressed location triggered a succession of failures at other locations, resulting in the downward collapse of the entire structure.
Dejavu all over again?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
https://www.eng-tips.com/viewthread.cfm?qid=470048
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Structural engineer sees similarity in deadly South Florida, 1981 Cocoa Beach collapses
"...the 1981 Cocoa Beach collapse inspired a law that required structural engineers and inspectors...to undergo a qualification program to 'enhance the quality control and inspection during construction of 'threshold buildings.' ' Such structures include those over three stories or 50 feet or built for more than 500 people."
Unfortunately, both of these buildings were under construction at the same time, so the additional regulations came too late for CTS. It would also appear that those lessons may well have been lost on subsequent inspectors over the years, if Surfside's questionable repair approvals are any indication.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I like spsalso's plan. He's just missing some whistles and hand gestures.
Edit:
The local aggrigate mines in the area are Limestone mines, especially if it came from Cemex.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
@Vance Wiley
Here's that link again
https://www.govinfo.gov/content/pkg/GOVPUB-C13-c3d...
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Be careful what you ask for? Are you sure you want all the "do-da's" and powerpoint guru's to invade a forum that has been lean, mean and focused?
Now that I have been exposed, I guess I will have to reinvent myself again. Perhaps this time Demented2 ? or perhaps SFDoDa ?
I too like spsalso's plan....They were working on wrong side………
Edit: Back to CTS Aggregate.......
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I went through the Oct 14 board minutes that Optical98 provided [https://s3.documentcloud.org/documents/20985354/20...], where the images of the cores samples are shown, and I found no mention of the cores being made particularly to inspect previous repairs. Is this core location requirement coming from somewhere else, and if so do you remember where that may be found?
A couple of highlights from the board minutes (for those who haven't already read them):
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I caught on day 1. Pretty sure others have known for a while. :P
@TheGreenLama
They weren't to inspect previous repairs. Some of the cores just happened to fall in the location of old repair work, especially those taken from the pool deck and lobby driveway. The concrete started to fail within a few years of building completion due to corrosion with rebar and spalling and failed or no waterproofing. 2 main restoration projects were undertaken, both of which were jobs that failed or were never completed. The Morabito work would be the 3rd main project going at some of these areas.
Precision guess work based on information provided by those of questionable knowledge
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The google search was "Florida limestone aggregate concrete structural strength"
Effects of Coarse Aggregate on the Physical Properties of Florida Concrete Mixes
Also, please see the attachment: (everything you could want to know... ...I got as far as the "Mohr circles" and got lost...that was on the first diagram.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thanks. That's what I figured you meant, but just wanted to make sure.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
(the title sounded like an old article, but much of the content is new and in perspective of the whole.)
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Am I looking at this wrong? Shouldn't it be 4% or 8% maximum regardless of splice? Just because you double the rebar during a splice, does not mean the columns rebar percentage maximum should increase.
The two values should be the same right? Just the column thickness should be based around the splice percentage and reduced rebar elsewhere.
Is it possible the code is wrong with 4%, 8%? How is the code today?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Charlie - I scanned well past the Mohr's circles and found only soil/rock(?) strata information for piles and foundations. Nothing addressing aggregates for concrete. I did find what I think is the source for concrete used at CTS - it looks just like many of the pics of crumbles and broken columns and slabs.
It is titled Figure 2-3. Newberry quarry excavation (Paul Bullock 2004; FDOT Public Report) and is found on pdf page 25 of your second reference -https://files.engineering.com/getfile.aspx?folder=...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
You could also just go with “sharp and forthright.”
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Takeaway:
Florida uses oolite and Florida limestone for structural concrete.
Memo to self: NEVER get involved in concrete in Florida.
My concern remains about how these aggregates weather under fresh water conditions, acid rain, and coastal environments.
If you see anything about durability of Florida concrete, please let me know.
Thanks again,
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Well...FDOT thinks it's a problem worthy of research...
See Attachment:
(more to come, only one attachment per post (as far as I can tell))
Actually no more to come, one article about using electrical resistance to measure durability, but that's all
Electrical Resistivity of Concrete for Durability Evaluation: A Review
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
That is what the code is saying. 8% is fine. But if you need to lap anything you are going to have to double up bars in the lap regions, so to remain below 8% total, you can only have 4% in the sections either side of the slices. In other words: if there are no splices 8% is fine, if there are splices, 4% max either side to remain below 8% at splice.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
It looks to be 3 column lines from south edge-- 12.1 --and about 2 west of pool--between L & M.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
If you wish, I would be glad to upload any or all of the following:
1. Performance Improvement of High Early Strength (HES) Concrete for Pavement Replacement Slabs
2. Effects of Blast Furnace Slag Characteristics on Durability of Cementitious Systems for Florida Concrete Structures
3. Development of Calcined Clays as Pozzolanic Additions in Portland Cement Concrete Mixtures
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I prefer considering myself 'Vintage' rather than archaic.......
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I'm glad someone is keeping a watch on the research and investigation.
Please like and comment on the video. They can use the support.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thank you! I am so used to looking at the plan drawings and counting down from the top that it threw me off to see a different orientation.
I think plenty of us are no longer young whippersnappers.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Edit: It doesn't look like ground penetrating radar. Wonder if it's water related?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
(Anybody local have camera, will travel?)
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Starting about page 20, the attached presentation discuses
'Corrosion-Resistant High-Performance Materials' CR-HPM
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The key word in this is the word "Lap" which creates a zone with twice the amount of reinforcing. The comment specifically states the purpose of limiting the % of reinforcing is to avoid congestion and facilitate the concrete placement. I can see congestion and small spacings causing poor concrete at a lap section with too much reinforcing - 16% is a lot of the column area and bars will be close together. Some cases require the large aggregate be removed and the first portion of the pour be a slurry with higher cement content. Normal practice is to lap with the bars in contact and the dowels from below oriented to the interior behind the bars above and that helps a bit.
From the commentary "Longitudinal reinforcement in columns should
usually not exceed 4 percent if the column bars are required
to be lap spliced, as the lap splice zone will have twice as
much reinforcement if all lap splices occur at the same location."
I do not read anything there which prohibits a maximum of 8% "at any section" if the bars are not lapped.
The practical workaround is to use splice couplers and keep the bars aligned with the dowels from below. There will no doubt be some discussion of whether the added size of the coupler should be considered as increasing the percentage of reinforcing at the coupler location. I would say technically it does and practically it does not have to, therefore the working % for the column must be less than 8%. This can be fudged by splicing the coupler splices at different heights starting maybe one coupler height above the previous pour. This complicates things and probably should be avoided. BUT if aggregate size allows and mix properties of slump and consolidation efforts are successful, that should be allowed.
The best solution is to avoid highly reinforced columns and just make the column larger, thereby easing the difficulty and increasing the likelihood of success.
Perhaps this has been discussed within the Concrete Design industry and that would be interested to see. Ultimately the EOR is in charge and can decide whether to take advantage of the ambiguity or go conservative and increase the column size.
I would recommend a larger column if a design was closing in on 8%Ag working reinforcing. But then there are architects who want skinny columns.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
We will all thank you very much!
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Or its 4% down the length and the splice is a weak point at 8%.
Someone mentioned staggering the splice, sure, its possible, you have the start and end of the rebar at different points, such that you reduce congestion of rebar at any one point. Its a little complicated, but still possible.
The problem to me, is the splice occurring just above the slabs, and someone deciding they can't fit as much rebar from the slabs through the column due to congestion?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
There is a live cam but it only shows about 1/3 of what we want to see. When the vid was posted it was already gone. I'm way too busy to keep a close eye on that and there is not much to see most of the time.
Link
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
"the blue thing."
I think those are counterweights or stabilizers for the crane.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
They may have been assembling or disassembling the apparatus when the video was made. We may never know its final form.
Dynamic Load Testing (DLT)
Dynamic Load Testing is a method to assess pile load capacity by applying a dynamic load to the pile head (usually drop weight in frame) while recording acceleration and strain at the pile head. DLT is a high strain dynamic test which can be undertaken on cast in situ piles when the pile concrete is strong enough to withstand the stresses generated during impact. For preformed piles (eg. steel, timber or precast concrete), testing can be done either during or after installation.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The definition and the picture came from two different web-sites but from the same search. Couldn't tell you how it works or if it works on an old slab but I'm not getting paid enough for that. At least we have more pixels.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
In the case of splices in column bars, with bars in compression, the bar above the splice has some load - and it passes that load to the lap bar. So at the top of the splice the upper bar has 100% of whatever load, and the bar from below has no load. Half way down the lap the bars would have 50% each, and at the bottom the lower bar has 100% of the load from the above bar and the above bar has none. So, theoretically, the load being carried by reinforcing is the same throughout the splice length. Another 4% (lets say) of concrete area is lost but it seems the code does not address that. Other things are going on also, with the upper bar having 90% load (10% from top of splice) with a corresponding strain of 90% while the bar from below has only 10% load and strain - and there is some discontinuity in the relative strains in bars which are in contact. But the code does not seem to be concerned here. So, paraphrasing Brad Pitt in Moneyball, "when you get the answer you want, shut up". (Keep it simple.)
Compression bars at a splice could develop end bearing of maybe 5 to 10 kips - which is disregarded unless one is trying to save his butt.
It would seem to be proper to disregard calculating the column capacity by using the doubled reinforcing (eg. 8%) in a lap splice zone. After all, just above the lap splice the reinforcing drops to half (eg. 4%) and the column loses the stability provided by the slab or beams. This would seem to be a more critical place to check the column, if no frame action has induced moments in the column.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Here's a slightly-less potato-ey grab from that drone footage...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I cannot locate an on-line source for an ACI 318-77 code. Can you find one? I have looked for more than 4 hours.
Does anyone on this thread have one and could copy the Column Design section, which is Chapter 10 in the -14 version, and post it here, please?
I would like to verify the 4%/8% issue. If the maximum allowed reinforcing was 8% for splice zones in the ACI 318-77 version several columns are/were not code compliant at the splice zones.
If that is the case, special measures were necessary to ensure dense and well conslolidated concrete at those zones, and it seems the concrete for this project had little special attention.
The possible consequence would be low density or incomplete consolidation of the concrete, and possibly leaving voids and rock pockets at some locations. Most serious locations would possibly be at the top of the pile caps and locations where salt water could collect from whatever source - winds off the ocean, wet tires, or underground water.
Thanks,
EDIT ADD: Drawing sheet S-11 references ACI 318-72..ACI 318-77 should have been in effect when the design was performed.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
When I was referring the vehicle impact data, it was obvious that only a little bit more thickness of the columns was enough to completely prevent the issue. If an extra inch of concrete column thickness was enough to save nearly a hundred people from dying, isn't that worth it?
If we added up the total cost of an extra inch calculated into every dimension of the building, and that cost spread over 40 years. What amount are we talking about? Is the lowest common denominator acceptable here?
The code says this, so we won't do anymore then the code? Like I am sure that the code isn't there to put the bare minimum into your building. How safe do people feel living in a condo where only the bare minimum was put in to satisfy the "code"? Maybe the code should be set at a 4x amount that makes it super impossible for buildings to ever fall over ever again?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I believe you are correct. Lying in bed last night that was another option that came to mind. I've never seen this done, but this would be something entirely plausible. Below is video of an operation. I can't vouch for all the info presented. https://www.youtube.com/watch?v=ZWN5dO1U1ms Obviously they need to set up above an existing pile cap. Another pile test option is a static test.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
You do, within reason; columns are non useable floor space. You keep the same column size for several floors changing the amount of reinforcing and you can change the concrete strength, too. You want to keep the same concrete strength for all columns on a given level. I haven't designed a multi-storey concrete building for a couple of decades, but that's the way it was done; I assume it's still done the same for economy.
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 12
And yet I am not 100% convinced on my own theory. From your video it says the minimum pile exposure is 2 times the diameter. They may have found a way to get usable data even with a slab that would distribute the the impact over multiple piles or maybe they are using DLT equipment in a different manner or for a different purpose. I check the live cam at least once on most days if I have time, and never saw them while they were there. I'm pretty sure they only tested one or two locations if that means anything.
Edit: Live cam is missing in action right now, maybe they know I'm watching!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I clicked on:
INFORMATIONAL RESOURCES ON ACI 318-77
on that page, I clicked on:
on that page I found:
I clicked on:
318 Historical ACI Building Code Requirements (1908-2005)
on this page I found all the revisions of ACI 318-77
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Maybe they don't know we are watching?
Please like and comment
Let YouTube and Them know you care! Thanks
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
https://www.youtube.com/watch?v=bTK-Im3FQ3M
The narrator speaks of "drilled shafts" (a terminology not much used in this thread).
Drilled Shafts: Elements formed by creating a drilled hole into which structural steel and concrete is cast or placed.
Driven Piles: Foundation support typically using steel or precast concrete elements driven into soil with impact or vibratory methods.
I think that the Franki piles in use at CTS are sort of a hybrid, since their installation involves both wet concrete placement and driving.
Regarding ConeTec (as spotted by AusG), I found no specific mention of DLT on their website, but they are clearly specialists in doing geotechnical site investigations.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I don't do concrete design, but I suspect if I was, and I knew that a) I had to lap bars and b) the maximum reinforcement % was 8%; then I would design everything I knew had to be lapped with 4% reinforcement so it wasn't an issue / didn't matter where the splices ended up being.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
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 12
For test to be effective I would think they would have had to chip out fdn slab to expose a lone Franki pile (No comment of effectiveness of PDA on Franki piles). And it is likely that they are working in that area simply because it is away from the collapse event. Piles near collapse may have been damaged.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I was able to get to and now I just need to sell my house to cover the cost and I will be good.
In today's code, using lap splices, the max reinforcing in a column is 4% (as I interpret the code) because the lap splice zone is limited to 8%.
That may not have been the case in 1980.
In my mind I had thought the max reinforcing was 4% and the purpose was to prevent brittle and abrupt failures.
Today we have products which can flow and maintain strength and could be used in congested areas - there is a minimum limit dimensionally of course, and the cost rises. Another 2 inches on the column dimension or an extra 1000 psi on concrete strength would be less expensive, I think.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Drilling, and:
geophysical-testing
Including
MULTI-CHANNEL ANALYSIS OF SURFACE WAVES
So, maybe, drop the weight, and record the echoes???)
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
This ball of string has gotten away from me and I am trying to collect the ends to prevent leaving bad information here.
Thanks for the help.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Staggered lap splices are common.
Couplers are sometimes given as an option for contractors. I have a sense, though, that these are a costly option.
Using couplers for outside/perimeter column bars may be impacted by two things: maintaining minimum concrete cover (as a coupled bar now has an increased diameter); interference w/ the shear/confinement steel. You always want to situate your column steel as close to the edge as possible, and shear steel interference w/ coupled bars may impact the use of couplers.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
ACI 318: Building Code Requirements for Reinforced Concrete
It's Big
(finally got it to open, it's the 1995 version.)
edit: one may buy a used hardcover on Amazon for $120 +$4 shipping
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
If there are other chapters you would like, just ask...
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
My earliest edition is the '63...
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 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Found a PDF online that is labeled as a 1980 "Technical Release" for use by the USDA that is supposedly based on ACI 318-77. User beware.
https://directives.sc.egov.usda.gov/OpenNonWebCont...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Many thanks, and an old phrase "Much Obliged".
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I would normally agree with letting them know we like their content but this is not a youtube live cam. It is a NEST cam that is owned by the same people that have the drone video but they do not share a link for the NEST cam on their youtube page. If they want it hidden, I'm not going to draw extra attention to it. Some people really want to restrict sharing info with other people. I think the facebook page I was on is theirs also and they are searching for spies that are stealing their info and not giving credit to them. Something about a "fake youtube engineer" making videos with their research.
This post will self destruct as soon as you finish reading it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
https://skyciv.com/concrete-footing-calculator/
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I do appreciate the effort. And I will beware.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Building Code Requirements for
Structural Concrete (ACI 318-95)
and Commentary (ACI 318R-95)
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
https://res.cloudinary.com/engineering-com/image/upload/v1630272552/tips/ACI-Ch_10_dybsxp.pdf
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 12
August 25, 2021 Building Membership Council Governing Committee meeting
https://www.youtube.com/watch?v=RsVIqiBQjEM
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
You had already sent 10.+. Your clip of 10.7 and 10.8 carries over to 10.9 and that addresses maximum reinforcing in compression members ( columns).
It clearly states minimum As is 1%Ag and maximum As is 8%Ag. The comment recommends As max of 4% if splices are lapped.
Note that it is a recommendation. So if the columns at CTS have 6% reinforcing that was not a code violation - just ignoring a recommendation. And is not permitted in current codes, practices, or recommendations by several Structurals on this forum.
I can put this to rest now. I will not use more than 4% steel in a concrete column.
Thanks, everyone.
WAIT !!
Charlie - were the clips you sent from a 1995 edition of ACI 318? If so that leaves me wondering how the 1977 edition addressed this. No sleep yet - - - disregard prior comments herein.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
2. the posts upstream are from the 2014 version
3. I don't think it has changed much?
4. Chapter 8 is labeled:
"ANALYSIS AND DESIGN GENERAL CONSIDERATIONS ......... 318-77" <- I don't understand this?
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
More than a recommendation... those that 'Be' will rain down h*llfire and brimstone on those that mess with it.
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 12
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 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
https://res.cloudinary.com/engineering-com/image/upload/v1630296884/tips/p22_cppehu.pdf
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 12
edit: Nop, same hand written note (page 113, top of right hand column "UBC ZONES 3.4") in my 1995 and DIK's chapter 10
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I would be interested in knowing about the columns that failed.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
>>>>>Edit: More late-breaking news.
South Florida Officials Hold Discussion Regarding Safety Improvements Following Surfside Condo Collapse
Museum Preserves Surfside Memorial Wall for Building Collapse Victims
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
thanks...
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 12
Let me know if anyone wants it. I searched high and low and cannot find anyone with the "77" version who doesn't want $200 for a stinking PDF!
Also, I uploaded a video the other night where I added my graphic overlay of the parking garage over NIST's video of the empty garage floor "hockey rink", to aid visually what is going on at the site, and identify where ground zero is.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
ACI 318: Building Code Requirements for Reinforced Concrete
It's Big
(finally got it to open, it's the 1995 version.)
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
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 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Most likely the falling 12"x16" column M11.1 weakened or crippled the 16"x16" M9.1/M10 via yanking on the beam connecting them as the skinnier column was destroyed by the deck collapse, and shown missing in the tourist video. I think that the smaller column severely damaged the 16"x16" to the point that it made that now-weakened and de-rated 16"x16" column a few minutes later begin to buckle and crumble, now that they are no longer rated to do the job they have been doing up to this point.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The deck collapsed at 1:15 AM or so and the building collapsed at 1:22 AM, so about seven minutes elapsed between those two events. During that time witnesses say the building was shaking and rumbling.
Here’s the CTS Collapse Witness Statement Timeline for your reference.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
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 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
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 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Defunct and disorganized: Surfside town records detail woes of code, building departments
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
It has nice 3d perspective art for the floor plan, with location of the victims, and tears.
A vertical neighborhood: Floor-by-floor look at the lives lost and dreams shattered by Florida condo collapse
(maybe Maud will share the magic of how to make a link to bypass the firewall? Thanks)
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Miami Dade police have been keeping that place solid nobody goes in or out. And I listened in the other day to a Surfside Commission meeting where the entire Commission wasted 1/2 hour of time bickering back and forth trying to figure out why won't they let us in blah blah blah.
These people are totally clueless they don't realize that they are the subject of a criminal investigation and I think their heads are buried in the sand on this one. And the reason why they are the result of a criminal investigation is because like we've mentioned before here on the forum, all sorts of records are missing from the city!
And, they don't know if missing records are due to that former city inspector Ross Prieto who had the keys to the warehouse under his name, whether he is the reason they are missing but right now everybody is suspect including anybody that the city would hire even though Alan has a very good reputation in the business.
That being said, Alan did visit the sister property, the Champlain towers north which has almost the same floor plan, and he did take all sorts of core samples there and I guess we're waiting to hear back from the results of that, but so far he feels that building is not in any danger of collapsing. the scuttlebutt I had heard from over the years was that maintenance was completed in a timely manner in the north towers, as that homeowners association was more on the ball and when things broke down they fixed them there not let needed repairs sit there in fester for years.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
(only one attachment per post - Part 1
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I have processed ACI 318-56 into two smaller searchable .pdf files, Be careful with formulas, they have been thru a tortured process Adobe converted pdf to OCRed Word, I manually remove the shadows of the "gutter" between the pages of the book, Word saved as .pdf.
(only one attachment per post - Part 2
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Just Identify the page clearly, and I'll post its image...
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Here’s an archived version. This piece was never updated with final status info…it shows people as Missing who have been recovered Deceased. A vertical neighborhood: Floor-by-floor look at the lives lost and dreams shattered by Florida condo collapse
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Pros
A utility at archive.today takes a snapshot of the contents of a URL and stores it. This has several benefits, e.g. developing news stories can be archived multiple times as the story unfolds and information on the URL is updated. It will also archive an article that is on a site with a “number of free articles” counter on it. It will retain the archive even if the original URL is taken down.
Cons
Archive.today will not archive an article behind a true firewall requiring a login, e.g. WSJ, etc. Sometimes videos within the content will play and sometimes they won’t. Embedded hyperlinks may or may not work. Interactive graphics don’t work interactively…they will be static graphics.
Steps
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
So the columns that failed were overcrowded with rebar? This making them weaker then they should be? Its clearly out of code right?
What about the connection point with the beam under the planters? Also, exactly where does the splice occur? Is the splice just above the beam?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Beyond the firewall
A link in the article, that Maud posted just above: had slipped past me.
It has nice 3d perspective art for the floor plan, with location of the victims, and tears.
A vertical neighborhood: Floor-by-floor look at the lives lost and dreams shattered by Florida condo collapse
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I did provide a link to the '95 document that was already publicly visible and searchable on the web.
I also posted a link to Amazon's offers where one could purchase used editions. This is common in reviews of copyrighted material.
I believe my other posts have been links or excerpts.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
https://www.copyright.gov/fair-use/more-info.html
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Do not know about the beam to column joints or beam to beam joints. That is typically easier to use a vibrator and improve the density of concrete there.
Splices in the columns are at the top of the pile caps, and top of each floor slab. Details for this are on sheet S-3 (pile caps) and S-11, columns.
EDIT ADD:
Subsequent posts address rebar crowding - I would add that it has been suggested here that 3% to 3.5% is a practical limit. I agree, and suggest the extra concrete be used to provide more cover for the reinforcing, thereby also providing enhanced protection from corrosion, particularly important in coastal environments.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Gatekeeper of Broward’s building code skeptical that climate change affects buildings
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
But per the information you shared. I don’t think that posting/sharing or hosting (in the case of files uploaded to engineering.com’s servers)whole documents constitutes fair use.
Two of the factors considered in evaluating fair use:
In this case, complete works of different ACI standards are being distributed. In some cases, enhanced even to make it searchable and eliminate annoying artifacts left over from the stealing process.
It would seem this would certainly apply to the current code. Maybe less so to the older versions. Though, if ACI still sells them (or sells a higher quality (e.g. searchable version), it seems apparent it’s harming the market value.
Otherwise it would seem there would be entire libraries of these and other documents (like ASTM specs) just existing out there in the public domain.
I also don’t think that “I’m just sharing something that someone else stole” is a defense that a Professional Engineer should use. But maybe that’s just me.
Maybe the ACI documents are intended to be free. In which case I’m out in left field. But I always thought that charging for these standards was the means of recouping some of the cost for developing them.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Nop no flooding here:
Thursday Night's Rain Caused Street Flooding On Miami Beach
Aug 13, 2021
nor here:
Miami Beach areas already flooded as Fred approaches Florida
Aug 13, 2021
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I do maintain that:
1. Posting a link to their site with instruction to find their publications helps them.
2. Exposing engineers to the existence and relevance of their codes helps them.
3. A link to "stolen" ACI-318 is no different than finding that link in a google search.
4. The "clean-ups" were put thru Adobe OCR which corrupted the formulas, the heart of the work.
So go buy a copy
ACI Standard Building Code Requirements for Reinforced Concrete (ACI 318-63)by ACI Committee 318
$120.69
Hardcover · Used, Good
Only 1 left in stock - order soon.
Shipped from: Friends of Jefferson Public Library
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The ACI sells a thumb drive with every version and supplementary documentation from 1908 to 2005 (fully searchable) for $200 here:
https://www.concrete.org/store/productdetail.aspx?...
Including:
This site sells it at a slight discount for $178.65
By the time you’re done with it, that memory stick will certainly be treasured memento that holds a place of esteem alongside your other well-worn texts =)
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
It is best to proceed with caution. You don't want to put the cart before the horse. We don't know yet what happened, so we can't prevent it.
However, it appears that the building was built too low to begin with, which cannot be blamed on sea level rise, but you can start by building well above the current water table.
120 Years ago or so, the city of Miami was quarantined because of yellow fever. At http://digitalcollections.fiu.edu/tequesta/files/1... you can read an interesting account of how it was dealt with. It helps to read it using some historical perspective. A lot of very costly things were done but the mosquitoes weren't quarantined. You don't want to repeat mistakes. There is no substitute for knowledge.
In the epilogue, the Reed Commission is mentioned. That would be Major Walter Reed after whom the hospital was named when he died of a ruptured appendix.
Some of the treatments for yellow fever:
We need to get this right. In the meantime, more inspections can't hurt.
EDIT: It seems as if the building didn't meet code when built and the code has been updated since then, so further updates would not be specific to this tragedy. Since this is not my area of expertise, does code specifically address repairs? It seems to me that more focus needs to be made on all the repairs that were made to the pool deck. How are such repairs regulated?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I am familiar with that. What I was questioning was the "full depth" repairs to the pool deck or any other repairs that expose rebar. I don't have enough detailed knowledge to understand whether how the repairs are made is regulated. How does a "patchwork quilt" slab behave according to the models on which the structural calculations are made? I have more of a background in modeling and my concern is how does the reality of a patchwork quilt relate to the idealistic models of how materials are supposed to behave? Can the "code" (which is based on models) be honestly applied to something that may behave very differently than the idealistic models on which the code is based?
At what point does someone need to step in and say that you can't treat a slab like "my grandfather's axe: I've replaced the head twice and the handle three times"?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thank you!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Inspection is still put off onto the wrong hands in this state, but at least we have ACI 562 now.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
For example
Defunct and disorganized: Surfside town records detail woes of code, building departments
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
It has been downloaded over 1800 times. It is either 13 or 18 pages.
@Charlie - It could be a good thing to have all these in the library for this forum - while they are free.
Now there is the beginning of a code to guide(?) the investigation of building disasters.
Kudos to ASCE.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Very Interesting! Attached is the paper "Resistance of Flat-Plate Buildings against Progressive Collapse. I: Modeling of Slab-Column Connections"
I am sure the other papers are equally interesting too. I would say this one is a must read as far as CTS and RC flat slabs prior to 1989 code changes....
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I aam sure the attack attorneys will ask if the engineer followed these practices should they get involved.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
$49 Million To Be Split Amongst Surfside Victims, Families; Hearing Held To Discuss Future Of Condo Collapse Site
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
After what we know about the structural slab delaminating at the top reinforcement, I think that the only real fix would be to replace the entire slab? But your question about who makes that call, is a valid question.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
In the mean time:
Please find attached below:
Resistance of Flat-Plate Buildings against Progressive
Collapse. I: Modeling of Slab-Column Connections
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
https://www.nytimes.com/interactive/2021/09/01/us/...
Edit: Warning for some, No mention on Top First.......
Thank you for posting that particular paper! It appears my attempted post of this paper was a failure!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The Surfside Condo Was Flawed and Failing. Here’s a Look Inside.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Before 1:10 AM, there were "knocking" noises.
At T minus 12 (1:10 AM):
In 111, Sarah (office), Gabe (kitchen), and Chani Nir (shower) hear a loud crash, as if "a wall collapsed" in the condo above.
In the lobby, Shamoka Furman hears a loud sound that seems to come from the elevator, although the elevator throws no alarms.
At 1:15 AM, the deck collapses:
In the lobby, Sarah Nir and Shamoka Furman hear a "big boom." Sarah runs to the window to see "all the garage has collapsed...:"
In 111, Gabe and Chani, hear a loud crash.
In the elevator between the garage and the lobby, Nicolas Vazquez and Gimena Arcadi hear and fell the collapse.
Other than the Nirs, I believe only Ileana Monteagudo in the x11 stack survive. Ms. Monteagudo wakes up after the deck collapse.
What if, one of the balconies between the red lines below fails and falls, thus collapsing the pool deck. I hate to bring up the "falling object" theory again, but I am struggling to explain the "knocking" noises and the "wall crashing" before the deck collapse. What if the balcony was falling slowly, until it fell against the building, hanging by a thread and then collapsed to the pool deck, collapsing it and precipitating the rest? Just another thought.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
A good theory always starts with evidence and works towards a viable explanation without confirmation bias.
It could be correct but the balconies are not simply glued to the side of the building but are a cantilevered part of the floor slabs with lengths of rebar extending far into the slab. I don't see them having any more chance of failing in a way that would trigger a collapse than other theories that have much more evidence and seem more likely.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Also keep in mind that the knocking sounds went on for over two hours, and maybe longer. Chani Nir (111) heard them starting at 11 PM when she got home. We have no idea if Shamoka Furman or anyone else heard the knocking sounds in the lobby, or at what time the sounds actually started. So that 2+ hour duration would tend to favor of the slo-mo deck collapse pulling hard enough on a weak column idea over the balcony collapse idea.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Good view of the stairwell
View to the right shows elevator shaft - this must be where the blocks were falling from?
I finally found a good pic of the deck below the stairwell door to the pool deck, I hadn't realized the deck had collapsed under the planter, you can see right into the basement...and the planter is still hanging to the wall!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
What is that large round silver object?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Let me know if this helps, I have Power-point and have viewed pics on it, but have not Used PP for a long time..
The green lines are the planter and the red arrow points to the basement.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
What is your point of repeating what I already said?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thank you. I've gotten too used to snarky replies on here, lol.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Link: https://www.today.com/news/surfside-condo-survivor...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
But yeah splice requirements, punching capacity, shear capacity of beams, direct design method, column reinforcement and all are the same. The missing things in ACI 318-77 code were integrity reinforcement, different phi factors compared to today’s ACI, factored load combinations specified by ACI and all.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thanks. This resolves one question…we now know the Gonzalezes did not make it out to the hallway. The floor collapsed outside the bedroom door.
So this means we do not know whether or not their apartment door could have been opened.
I will update the timeline to clarify.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Congratulations on the credit you received on the NYT infographic of 9/1/2021!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Many thanks for the link.
The presentation is so "real" and complete it brings to mind something that has bothered me over the last 20 years or more - it MUST NOT be allowed in a court proceeding. It is too convincing.
All they left out are the concrete eating termites from Mars.
My point being it will be hard for a jury (there will be no engineers on the jury - particularly structurals) to believe they have not witnessed all the defects that that contributed to the collapse and deaths. The video will instantly make them something like someone who knew the defendant well.
Any attorney working against some point is working uphill already.
Hell, I'm convinced. And I have sat in the box beside the Judge and explained many things to Juries.
Thanks again for the link.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thanks also to:
Here is the shared code for the article above
The Surfside Condo Was Flawed and Failing. Here’s a Look Inside.
I subscribe to the NYTs and they let me share 10 articles a month free.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Any 'a thing falls and starts the pool deck collapse' needs to explain why 111 didn't mention it, as it would presumably have fallen right outside their window.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
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 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I too was surprised they left out the concrete…they could have quoted the demolition folks and mentioned the ratings the concrete should have had by code.
In St. Louis we have a lot of cases and a small, generous population, so residents are called to jury duty many times. I’ve been called four times, and served twice (once as foreman.) Anyhow, based on my jury experience, this infographic is indeed a jury spoiler.
One of the things I liked about it from the witness perspective is that they avoided the controversy over “which part of the deck fell first” by showing the collapsed area collapsing all at once. Despite what some people think, we have no collapse witness statement to support a deck collapse sequence. Each witness describes what they saw right in front of them…cars fallen into the garage as seen from the lobby and porte-cochere, and the pool deck collapsing as seen from 410. Instead of trying to establish a sequence of deck collapse, the infographic did a good job (at least to a lay person) of showing us the weak columns, the long span, and area left overloaded by the elimination of beams.
The infographic also avoids trying to define what the Nirs call the 1st Collapse…which we have struggled over in our discussions. It could have been any number of things, from any direction.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
"That would start with Finding the many boxes of documents the Town of Surfside seems to have Lost".
That is a fact worth noting, eh?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I'm not very familiar with the plans, but I can't find where this column is used.
Help!
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The south side of the building did not collapse as the slab failed in punch shear and damaged a small area of the column.But there was a beam there tie it to another column. The pics show the column with chunks missing.
So a beam attached to M11.1 tore away from the column and left it crippled. Seismic wave propagated to the weaker columns on the upper floors and punch sheared.
The main step beam needs to be examined as this actually held up the building.
If a joint ran through it that would be the smoking gun.
Also a planter box BM A could have smashed into M11.1 and severely damaged it.
Also the video looks like the collapse starts at the top 5 floors and caused the columns to buckle.
I wonder what shape the piles are in.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Scroll up 7 pages to S7 and look at the East side of the East stairwell.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
That 8x12 column you are looking for is gridline Column E on the "Basement Level Dimensions drawing", page 33 of 336. On that page look to where the vestibule is in the garage, and out in front of the elevators to the left you'll see the tiny columns with 8" next to them. These also appear on every other floor level page, sometimes with TC next to it, not sure what TC means
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
TC Could mean Trash Chute.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Those things marked TC are right next to a 30 inch diameter hole that ends at the trash room on the first floor. It looks like they are in the corners of a room that you enter to toss your trash so the trash chute opening is not right in the main corridor.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
You might be right then, I got a better view of it of Morabito's plans for the 40 year certification, here is the screenshot I grabbed, and it looks like TC is indeed the trash chute. On the architect plans from 1979 that I looked at it was not drawn as clear as this drawing is.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thank you.
Page 219 of 336 screenshots of trash chute and the "P" columns Charlie asked for:
Edit to add: TC is not an abbreviation for trash chute because I see TC used in other locations on these prints. I don't know what it means.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
You are correct. Try page 29 of 336.
Edit to add: TC stands for tie column. Page 38 note 9.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Lock it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thank you all for the help!
Thank you, for your offer!
I didn't know, that's why I asked!
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Between M and N, 2 & 4...
Woo! I'm glad I wasn't a construction supervisor on this job.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Well yes, but actually no.
My first post on this subject had all the correct information Charlie asked for.
Your first post, after mine, was the wrong columns, then you continued to try defending incorrect information and told me to be more careful about where I found my information.
"P" columns are different from "TC" columns in the amount of rebar and concrete strength for each floor.
And here you are still defending the wrong columns.
We done?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
A snippet:
"We see a privately owned collapsed building in Florida and a publicly owned collapsed bridge in Minnesota as two distinct problems, but in a fundamental way they are not. In one case individuals sweep pronounced problems under the rug and show a moderate cost savings. In the other case an entire nation falls trillions of dollars off the international pace of infrastructure investment and meanwhile creates a tax incentive so a hedge fund can erect a pencil-shaped skyscraper in Manhattan with a $100 million penthouse and plumbing that leaks because the building sways in the jet stream."
The Surfside Condo Collapse: A Brief Forensic Study of Missing the Point Entirely
https://thebanter.substack.com/p/the-surfside-cond...
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
https://mwi.solutions/technologies/wms-wcs-and-oms...
If this is just an ad, please flag it thanks
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Also. On the failed bridge he mentions: wasn't that a straightforward mistake of fabricating the gusset plates out of thinner than specified steel? Quite the contrast to the condo.
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I also got some video across the street from the Champlain Towers N building, which is 3 buildings north. I basically duplicated the famous tourist video in the daylight, and got to see a much better brighter view of the columns in the afternoon light, as well as unobstructed views of the columns when a car came out and the gate went up.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Then go to the hotel and ask the staff to show you a unit on the south side (overlooking the pool?) shoot some video and tip them well ($1 bills don't cut it anymore)
Looking forward to seeing the results on YouTube!
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
For example, in 2012 they passed a law requiring condominium boards to take out fiduciary bonds, which protects us condo unit owners if people from the board of directors take off with the money or siphons away cash.
And in one of my condos where I was trying to sell the unit, the deal fell through, because the lender for the buyer asked for that proof of fiduciary bond and did not get the proof of a fiduciary bond. Then we found out that there was no bond and we were furious that the president of the HOA had not secured any of that insurance. But luckily the buyers brought in a third buyer and paid cash for the unit which ultimately saved the sale for me.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Can you post the pics?
Did you any bomb sniffing dogs?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
If you go back five or six threads, you can review the discussion about a car hitting a column. When you review the Collapse Witness Timeline, you can see that we know that the following people used the garage immediately prior to the collapse:
<1:15 Nicolas Vazquez and Gimena Accardi (who were in the elevator when the deck collapsed)
~12:50-1:00 Eric Zion
~12:30 Sarah Nir and Gabe Nir
What we do and do not know:
- No one has volunteered any information about seeing or causing damage in the garage at the time they were there. No interviews to date have included questions about the garage.
- No one has volunteered that they heard any knocking sounds (which were heard in 111 from 11:00 PM on) while in the garage. Vazquez does say they heard a couple loud cracking sounds several seconds before they got on the elevator.
- We do not know what parking spaces any of them used. Depending on where they parked, it is possible for damage to have occurred outside of their lines of sight.
- There may also have been other garage users we don’t know about.
Basically, at this point, unless new information is revealed, any speculation about a driver hitting a column is just that…speculation.RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I will tell you today I got video outside Champlain Towers North of the view that tourists video was shot, but mine is in the daylight, the gate was open and we can see all the columns, where they should be, and it will put to rest all arguments people have on the tourist video as to which columns are where and what is missing.
I won't be posting my Champlain Tower pics or video that I shot today until I upload the final produced video onto my YouTube Channel, to prevent other channels from stealing my photos and video and getting a first-mover advantage on it, or run around trying to claim it was their work like we have witnessed lately.
I am also miffed the NYtimes appeared to use a lot of my early work and deductions without giving me credit I know they said: “some engineers said”…. It seems they were doing a research paper based on other's work, they even gave Miami Herald credit for their Aug 8 article but not the rest of us.
As far as I know, my channel was the first to offer a minute-by-minute timeline in video form on my first How IT collapsed video, which got 5 million views and a few press interviews for me, so I know they were watching my content.
Then Maud came along and did that awesome spreadsheet of the timeline which I now use because it has much more granularity and clickable evidence links to back up data points. Very well done Maud. It was obvious they referenced that spreadsheet but I did not see the credit to Maud.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
This aligns exactly with 911 calls, from 1:22 AM you can hear the building collapsing in the background.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
But, the Champlain Towers North and South are NOT carbon copies. Many people think they are the same because many framing plans are the same. But Champlain South has 12 units per floor, and Champlain North has only 10 units per floor. The floorplans of the units are different, even though the pool deck, and balconies, and look of the buildings are pretty close. I got photos of the drive-up porte-cochere and the above-ground parking deck, and the pool gate from the parking deck. The pool is now closed indefinitely as they do their 40-year inspection.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
ABC News quotes the 1:18 AM timeline. This is in the Data tab in the Timeline spreadsheet.
Edit: This one is actually better. NBC News states the Before video was time stamped 1:18 AM, and the After video was time stamped 1:27 AM. I just added this to the Notes in the timeline.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Max building fail in Miami
This is consistent with what I saw in my frame by frame analysis. I find it difficult to explain the strange angular brake to the east of the stairwell shear wall, but it appears to be what happened.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Miami condo collapse: ’No reason for this building to go down like that’
The original Twitter post
Another graphic for the Miami/Surfside condo collapse,
Original Image:
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Its really simple, car hits column, its attached at the top by a beam from the direction of impact. It has every reason in the world to bottom shear. 40km/h is enough to take out pool deck column 12x8 inch.
Were any bodies recovered from inside cars?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
As far as I know the only 'evidence' for this column being 'missing' is the TikTok video? If you look at that video, you also can't see M12.1 - but we know that column did in fact stand up and the slab fell around it, hiding it from the camera. I don't believe you can be sure that the same isn't true of M11.1. In the cleanup videos you can see that the bottom rebar for M11.1 is there after column and debris removal, and doesn't look any different from that of the other columns nearby.
> @Jeff - Champlain Towers North and South are NOT carbon copies
In particular according to some people in previous threads, the slab step at the building side of the pool deck isn't there. I'm not sure the M9.1-M11-1 beam is either. But the column layout is the same so it should be good for the parking ramp video if you've lined it up correctly.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Well you can't put to rest all arguments until you after have heard all arguments,(and you know I have one).
So far nobody has said much about the fact that the collapse shown in the tic-tok video has taken out the lights beyond the ramp. I have been in parking garages with rows of lights off and it is freaky how things like columns just disappear when there are no lights shining on them.
Is there any chance you could get some video of a garage or other room with rows of columns and show the effect of turning off lights towards the back of the room?
My point is that I believe all the columns are there but we can't see them with the lighting that is available. This also makes it impossible to see how much damage they may or may not have.
Your post got a star from me. Excellent logic.
All bodies or remains have been recovered and identified.
I have read reports stating that all victims were located where they were expected to be.
No extra bodies or remains have been found.
The smallest column listed for the basement level is 12x16, not 12x8. I even tried to scale off the prints to confirm this.
Perhaps this mystery car had a flux capacitor installed.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Is the idea is that something hit it with enough force to shear it flush at both the top and bottom and knocked it completely away?
Or did it get laid over at 90° right at the base leaving it even with, and parallel to the ground? Shearing all of that rebar cleanly at the ceiling.
Those columns have proven to be like box of spaghetti noodles as far as the rebar goes, but all of that has disappeared too.
If the column has been hit (or otherwise damaged) I would have expected to see a buckled or stoved mess where it was. Not nothingness.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Exactly right.
It must be there, either still standing, leaning, or in the debris pile, but I suspect we just can't see it because of the lighting. And no video from CTN taken in the daytime with all the garage lights on will convince me otherwise.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thank you, Jeff! I am a big fan of your overlays, because they reduce confusion and help develop a common understanding of what is where.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The only structural scenario I see now is the beams holding up the planters torn chunks of concrete from the main step beam which held up the building.
I have not found any sections showing how the BM A's were tied into the step beam.
One plan shows a 2-6" beam and another a 1-6" beam. Also there was a large load on that beam from a weight room.
The BM A's also tied directly in to the columns K, L M and probably damaged them similar to the damage on the other South east punch shear beams.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Miami-Dade’s economy depends in great part on real estate. They need to preserve the belief that local properties are safe to buy, sell, and live in. To keep their real estate market viable, they are highly motivated to assure that the collapse of the CTS is blamed on anything other than environment, location, and building age. After all, there are many other buildings just like CTS all over Miami-Dade, and residents are rightly concerned that their building has the potential to be another CTS.
IMO, the County hopes to build a case for criminal negligence by the Town of Surfside and/or the CTS Condo Board. The fact that the Town of Surfside immediately engaged a very highly regarded forensic engineer put Miami-Dade at a disadvantage, because Kilsheimer will focus on a thorough, correct analysis whether the County likes it or not. So they want to keep Kilsheimer out of there so they can buy time to try to build a criminal negligence case that will take the focus away from the realities of aging concrete and steel structures in a highly corrosive environment on a barrier island threatened with imminent sea level rise.
That’s the way I have been looking at it, but I am not local.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
While presumably trying VERY hard to stay away from the concept of Shoddy Construction (see: "...many other buildings just like CTS..."
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
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 12
Negligent manslaughter (Florida): the killing of another person through gross negligence.
The condo board is a tough sell. They're just a bunch of clueless non-professionals. But the city: a person paid to act in a professional manner who......
And if that person could be shown to have been acting in a manner accepted by the city,......
spsalso
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The city? Or the licensed professional structural engineering firm that was paid $500,000 to assess the condition of the building, analyze the as-built conditions, identify structural deficiencies, and design repairs?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I noticed while filming the Champlain Towers South debris site yesterday that all the column rebars were pretty much intact coming out of the garage floor, mostly the rebar is vertical. But look at this photo where I pointed to column M11.1, the column most of us think brought the building down when the pool deck collapsed against this column. This is the column underneath that planter, 20 feet outside the building wall. Look how bent and twisted Column M11.1 is, and all the damage on it, hardly anything left. Everything always seems to point to this column.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
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 12
I suspect that since then they've cut the rebar to take it away for analysis because they think there's something about that column too. Which most of us here agree with, I think, but it's not as simple as that pic makes out.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Jeff Ostroff...better images of the column in question. The way it's curved, looks like something ran into it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I wish that M11.1 rebar was the cause of the millennium tower sinking, but alas, they cut the rebar and the tower is still going down, down under the 22 inch limit they set...
We have photos of the basement when it was first emptied, before the excavator tore out the columns. let see what M11.1 looked like then. Thanks!
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
In case it's not obvious. Sarcasm.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I tend to think that more closely resembles a column that buckled and subsequently had 12 stories worth of building materials crash down on it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
This is the first image from the surveillance CCTV...
Now the camera is warmed up...
Central section falling, East section, not so much.
Central section still falling, East section, still not so much.
First clear evidence of east section floors tipping next to center section.
First clear evidence of floors tipping east of column (j13?)(sheet P4 of 11) 1979 plans pdf 10 of 336.
N10 (sheet S9 of 14) 1979 plans pdf 27 of 336.
column (N10) continues falling, roof line appears intact?
Last frame I've downloaded.
edit: Sorry, I forgot to attach the power-pointy file: (It' set up as a slide show...)
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Sorry, I forgot to attach the power-pointy file: (It's set up as a slide show...)
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
We can more accurately surmise that the rebar is not GREATLY corroded - it took some severe bending without snapping. Thus shifting focus to concrete quality at the time.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Look at the red arrows on my OP. You are looking at the wrong rebar.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Re 'missing' column - @Spartan5 pulled this screencap from a site video in part 8. You can clearly see M11.1's bottom rebar sticking up like all the other columns, so it certainly wasn't 'missing' up to a height of about 3'.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The rebar sticking up in the right hand square is from column 27, otherwise known as column M10. The pile was pushed from M11.1 toward the drive ramp before this photo was taken.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Rofl, someone can't count. 9 (skip a column) 11.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
You evidently missed my point. I know what rebar you are pointing at. I'm merely pointing out there is a ton of other rebar equally (if not more so) damaged, and therefore how contrived the vehicle impact argument is by just picking out the bent rebar which supports that 'theory' whilst ignoring all the other equally damaged rebar all around the site.
Did something drive into all the other rebar which bent those too!?
Can we please just put the whole vehicle theory to bed. This building wasn't brought down by a car.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Of course velocity has a large effect on impact damage. Perhaps a vehicle traveling at 88 MPH with a net force of 1.21 jigggawhats of energy. That just might be enough to vaporize that tiny column and it would explain without a doubt why no car was found against the column.
Check your time coordinates.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
M11.1 is a bottom shear. Find me a single photo of its intact rebar at the bottom.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
New theory: crane operator put a car full of tar paper on the roof (because it was easier to lift the whole car instead of unloading it first). In doing so they damaged the parapet wall ever so slightly. They had planned on loading old AC units onto the car to be lowered down with the crane at a later date.
While driving the car around on the roof the night of the collapse, one of the engine rods started to fail (loud knocking noises). But these laborers, being the really bad coked up Floridian type, kept driving it anyway.
The car then threw the engine rod through the block. It spun out on the oil slick, and crashed through the previously damaged parapet wall.
These guys, not being total f-ups, had considered this could happen and had tied the car off with an extension cord to a roof anchor. The roof anchor, having been poorly installed because they were drunk, failed to arrest the fall of the car. This was all signed off on at the highest level of town officials.
The car, laden with ac units and tarpaper tolls, plummeted to the ground trailing a long length of cord and a roof anchor (maybe more than one, we can’t be sure about that).
It smashed through the patio after glancing off of a planter which redirected it at a 45° angle right into the base of M11.1, totally obliterating it, and leaving behind the telltale u-shaped hook in the regard one would expect of the bumper of a Volvo station wagon.
It’s all there in the pile that has a few cones around it. PowerPoint to follow.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I think the ones sprayed with red are the columns used for demo.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The single bar at the first photo looks like a single #4 - maybe a #5. I cannot tell if there were more bars. That is far less than a structural column would have used.
In the second pic the worker is holding a bent bar of similar size. Not sure why that piece is of interest.
If that is a piece of a wall or jamb or infill cmu then I can see a vehicle impact causing damage.
But if that were a structural co
lumn it should not have been important to the stability of a 12 story concrete structure and loss of that less than significant capacity should not have caused a collapse.RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The building was making failing noises for two hours before the collapse.
Did the "vehicle" hit two hours earlier and nobody saw it? Nobody reported it.
No vehicle was ever found crashed into a column.
Can you obliterate a column and still drive away?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Find me the damaged "vehicle".
I found your research. Your "facts" leave a lot to be desired.
It used computer simulations for the column and car and said: "A shear fracture occurs at the joint when the speed exceeds 40 km/h for columns with dimensions 400 mm or less"
Shear fracture does not equal displacement.
A different study I found said: "The occurrence of plastic
deformation in the car determines the importance of using of a real car in the
experiments instead of a rigid projectile. For crash tests at high velocities large
plastic deformations in the car are predictable but this is not so obvious for low
velocity impacts".
Link
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
That column wasn't numbered was it, it was between parking spaces?
Is it behind these?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
EDIT - Nope - Sheet S2 shows it as the next column north of one marked 40/43?. I cannot read the number painted there - maybe 38?
EDIT 2 - the pool plaza columns are designated "N" and 12" X 16" with 4 -#7 rebars. One must interpret the note for concrete strength - it could be 3000 psi.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
42 and 40, 28 is behind 40
I can't see a number on the column behind 42
Yeah, I think we're looking for the column behind 28, and it's under the rubble.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
There were indications that the generator room floor was weak, they intended to reinforce it for new equipment..
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Scroll up to the last picture Jeff posted and put an eyeball on M9.1. Does that look plumb to you?
The generator is on the opposite side of the building from where the collapse started and was strong enough for the old equipment that was still in place. There is no evidence of a "vehicle" hitting the generator.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
And this is precisely why nobody should be using the condition of the column stumps or any other objects in these pictures to support any hair-brained theories.
Sorry about the vehicle jab, it was just the main hair-brained theory of the day.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Any investigation will be looking at objects in the pictures.
I try to stay open minded when presented with theories or maybe not even theories but a desire to talk thru an idea objectively. And I always appreciate the same courtesy.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The investigators were there for the entire process and documented every piece of evidence as it was uncovered. That is far different from a snapshot in time with almost no context. Like taking video through the fence weeks after the site is cleared.
I keep an open mind too but there are limits when the flaws in the theories are so obvious.
You want to discuss how it started with the generator? Go for it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I highly suspect there are only about 6 people posting on this entire forum, each with as many multi-personality sock accounts they use to derail any serious concepts or convos.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
M11.1 did not puncture shear, so where is it? A car didn't do it, then how the hell did it collapse? Was it the one pool deck column that managed to survive a similar fate?
Its ground zero, what happened to M11.1. Find me this column intact.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
What evidence shows M11.1 did not puncture shear? It could have been the first one to puncture shear but we can't know for sure because it got buried under 13 stories of rubble. If the damage didn't happen at impact, did it happen a week later? Maybe before the impact?
(please excuse me while I switch accounts, and personalities because... uh... reasons)
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Answer:
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
That’s been the approach to this here for the last ten threads or so. It’s all most have at this point. Barring any other videos or photographs from that night, it’s all that there’ll be for some time.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
You will have to credit others for identifying the items. I can only claim the creative writing behind the theory.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Cars hit stuff, I know one person who wrote a car off on a column. So it does happen. 40km/h is a slow speed, and between the column and the entry is like 100 foot downward slope, my car could do that just rolling naturally without any gas.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
LOL, You're not even close to reality. Let's find some real numbers and see what it works out to.
From the prints we have a grade level of 10 feet 10 inches. The garage floor is 2 feet 2 inches which gives a drop of 8 feet 8 inches.
The ramp length from the property line to the bottom at column line 8 is only 83 feet 4 inches.
Well I'm not smart enough to figure out rolling and wind resistance for your Australian hooptie and how to apply all that to acceleration on a ramp, so I skipped that nonsense and found a free fall calculator online and the numbers only come out to 26km/h. Surely the acceleration on a ramp will give a much slower speed than free fall.
Feel free to check my math.
And please share with us your evidence of a real car and how you determined it was going precisely 40km/h.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Also if someone can do calcs on this beam with a cantilever moment of the deck and planters added to the other loads?
The columns appeared to be the strongest element in the building.
They are a red herring and performed way beyond capacity..
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
> M11.1 did not puncture shear
What's your evidence for that? M11.1 was buried under the debris of the initial collapse, and then also by the eastern section, and during the clearance heavy equipment was dragged all over it.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
In any case, I will agree with you that maybe those aren’t AC units in that picture. What else do you think it is they could have loaded on the car before it lost control and drove off the roof?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
We know that some of the columns were (at best) of marginal size as originally designed. In many cases they appear to have had too much/too little rebar. Concrete was of questionable quality. Pavers/planters/water added additional weight, and provided access for seepage of water. Previous repairs are highly questionable.
Now, consider the possibility that one of the tenants is not a great driver, and occasionally 'nudges' the column next to their parking spot as they are parking. Maybe it happens once, maybe it happens a dozen times over the course of a year or two. There's little visible damage to the column, maybe a chip or two on the corner--but is the impact/vibration enough to internally crumble already damaged concrete, and perhaps loosen it from rusty rebar? Could the structure have been so bad that one little bump (or a series of them) have been the straw that broke the camel's back and brought the whole thing down?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Miami Condo Collapse: How A Pool Deck Brings Down Buildings
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
M11.1 is two columns distance from bottom of ramp. Its perhaps nearing 153 feet. Suggesting that the car needs to reach 88 miles per hour to damage a column is incredible.
I am not suggesting the car cleanly blew out the column at freeway speeds. I am saying the car hit the column at maybe 40-50km/h. You know, its late at night, a fee drinks were consumed. An older person is a little bit intoxicated. Old people suck at driving. They are coming down the ramp and the foot taps the wrong peddle.
Impact occurs. Its not enough to instantly destroy the column but its sheared at the bottom a few inches. Rebar at the bottom is broken from rust and the impact. The pool deck was already in a bad state. Somewhere else, another column punching shears, then another. Its a slow progression that maybe takes an hour or more. The sound of this slow progress can be heard in 111 its directly above the area.
M11.1 did not punching shear, because it was damaged before the pool deck collapsed. See, most the punching shear columns remained intact due to the protection the holed deck created. The deck collapsing held the columns pushed through it. M11.1 didn't punching shear, its fallen on its side. Why? The beam at the top prevented it from going through? It buckled, collapsed sideways. Its shear occurred at the bottom. Nobody has a photo of its bottom rebar intact.
In fact there is barely anything left. You think maybe the rebar was brittle as hell? Maybe water had been leaking down it and destroyed it?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Yikes with the blatant ageism there!
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
The large object immediately behind column 27 (column M10) is the object that SFCharlie noted had only a one foot diameter hole and that I conceded was not an air conditioner. Notice that this object has four mounting feet as I have shown in the annotated version of this same photo below. These four mounting feet suggest the object is associated with some kind of high torque application. Now you tell me what this object is and how it got there. I expect whoever took this photo will have the same difficulty of explaining this object.
Notice that behind this object lies a metal framework with a hole in it that is about twice the diameter of the hole in the first object. This would make it a candidate for the air conditioner that has been discussed at length already. Also notice that to the right of this framework lies what I have identified as a hexagonally-shaped weight on a rod. This object is seen in the TikTok video as shown in the photo below. Also seen on the debris pile as well as in the TikTok video is a metal sprinkler pipe and an object I have called a metal rod in cement. The TikTok video even shows shadows of these latter two objects. Now, you tell me how these objects got there.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Might you attach the power point, please?
My aging eyes can't make out what this blog does to photos.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I’ve enhanced the relevant portions for you:
Part of me feels badly for posting these things given the serious nature of the incident. But the rest of me can’t help but draw attention to some of the craziness that is being taken seriously.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Also, if you want clearer pics of the rubble, go to Getty Images and search CTS Collapse pics. Markbob, do that.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SFCharlie, see attachment.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I was silent from August 21 until September 6, when you resurrected your ridicule of me by re-posting my own previous posts above. Why do you insist on abusing people instead of giving your own theories and defending them? Do you enjoy playing god instead of trying to come up with your own valid engineering solutions?
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I’ve also posted my ideas. Much is awash in this sea of lunacy though. SFCharlie, for instance, missed my posting of the NIST footage which opened, I believe thread 8, because of all of the nonsense about roof anchors and a pallet of 200 tar paper rolls bringing the building down.
Playing god???? In what manner?
Engineering solutions? We haven’t even identified the problem yet.
But I think I found something that matches your sketching. The smoking gun perhaps:
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I agree with Markbob, this ridicule of others needs to stop.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thanks MarkBoB2 and thanks for the attached file.
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Well, the comment about 88MPH goes along with 1.21 jiggawatts. It was a movie reference that apparently went over your head.
“I guess you guys aren't ready for that yet. But your kids are gonna love it.”
Back To The Real World...
Some of the posters here are so locked in to their ideas that I'm sure they will never believe the NIST reports when they come out. They will end up as our very own Champlain truthers.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
A Brief History of: The Sampoong Department Store Collapse (Documentary)
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Maybe this isn’t the parade grounds. I’d be glad to exit stage right if there were another thread that was limited to the posting of new information from reputable sources and other actual engineering information in lieu of all the iSpy, fantastical conjecture, and WAGs we have the last ten threads here.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
My opinion is that the collapse was precipitated by the deterioration of the concrete in the pool deck. Although no test results from cores have been revealed I believe that the concrete was so weakened by the ingress of chlorides from the environment, lack of proper waterproofing and lack of proper maintenance, that :
1) The slab could no longer act in an elastic manner as designed by the ultimate strength method. Concrete finally failed in compression in a sudden manner instead of the steel failing in an elastic manner allowing redistribution of loads before failure.
2) The severe weakening of the concrete and compression failure led to complete loss of shear strength at the columns where the top of the slab was open and confinement in the bottom of the slab giving most of the shear capacity was completely removed.
Even without a sudden major triggering event the added surcharge DL on the deck due to an added layer of tiles and and waterproofing/sand layer along with any ponding due to excessive rain and lack of drainage of the deck and planters probably contributed. The deck so weakened only required some minor trigger to cause the collapse.
I believe that actual concrete tests will show that the insitu concrete in the deck is about two thirds to three quarters of the specified strength. This is also probably the case for the columns just below the pool deck and just above the parking garage floor.
Poor design, faulty construction and quality control, and lack of proper maintenance all contributed with all of these factors directly or indirectly involving the architect engineers and building officials. Just my humble opinion. Now all of the posters have something to criticize from the structural point of view.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Maybe if I had led with a gentler intro, I would have gotten farther.
I'd be delighted with the posting of new information from reputable sources and other actual engineering information.
Please stick around and bring on your ponies!
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Myself and others have postulated this same general theory, and have presented it across several posts that can be found in the first few threads of this topic:
-questionable design and execution of a highly-sensitive structural system (two-way flat slab susceptible to a punching shear mechanism that is inherently magnified by moment imbalance)
-an unforgiving environmental exposure that pours water and chlorides into the aforementioned structural system
-suspect quality of construction and construction materials
-non-existent periodic assessment/maintenance
.
This boring, vanilla theorizing has long since been buried by what seems like an incessant stream of rubble pile photo-analysis and other sensational musings, some of which I honestly can't believe are even being entertained as legitimate thoughts.
So a sincere thank you for bringing back this plausible/probable logic, despite the fact that it is clearly not spectacular or sinister enough for an increasing number of posters on here.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
It is not my intent to highjack this thread - I just have some items I wish to comment.
If anyone objects, I (or would hope, the powers that be) will take down the post.
The other night I watched CNN Films Present: 9/11, the Peabody Award winning documentary that was to be about a New York City Fire Department probationary firefighter but ended up being a minute-by-minute portrayal of the attacks from the perspective of the first responders who answered the call.
I was very moved. Kept thinking of CTS souls.
The doco triggered me into search.
“Falling Man”, photograph taken by AP Press Photographer Richard Drew. Controversial, and drew much criticism and anger.
“Desperation Forced a Horrific Decision” by Dennis Cauchon and Martha Moore, USA Today, Sept. 2, 2002.
I do not provide links here, because I leave the search decision to readers. Not my intent to be ghoulish. The subject matter is personal.
I kept thinking of New York’s Bravest going UP a 44” stairwell saddled with 50 lbs. of equipment and panicked people going DOWN. And some disabled, and some feeble.
“Federal authorities reported that during the designing of the towers, the Port Authority dropped plans to use an earlier building code that would have required six stairways in each tower, and turned for economic reasons to the more lax requirements of a later code that required only three stairways. By building fewer staircases, it could make more of each floor available for rent.”
-NY Times, Sept. 10, 2004
https://www.govinfo.gov/content/pkg/GOVPUB-C13-8da...
Chapter 10 > 10.2 REQUIREMENTS FOR A FOURTH STAIRWAY (Pages 159 -160)
https://www.history.com/news/world-trade-center-st...
Sadly, learn from mistakes - fire protection for steel, firefighter-communications systems, sprinkler supplies, elevator use…
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
I would encourage others with a different failure mechanism to reiterate their theory here; many have talked about over reinforcement of columns but did it result in failure in a particular way.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
2. Core were taken in 2020 and (some) results were presented to the apartment association and can be found in "Minutes of BOARD OF DIRECTORS MEETING held Wednesday, October 14th, 2020 at 7:00 PM".
I understand that more core were drilled and someone (Demented? or YouTuber BuildingIntegrity?) has found photos of them, but I don't know where?
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
(hidden on the plan of work performed)
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
"Minutes of BOARD OF DIRECTORS MEETING held Wednesday, October 14th, 2020 at 7:00 PM"
in the City of Surfside Archive, but NPR had a link to the .pdf in a memo sent to the condo board in October 2020
SF Charlie
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RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Please allow me to move the discussion to Miami Beach, Champlain Towers South apartment building collapse, Part 13, 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 12
Basement Floor (lowest level below-grade)
o Perform GPR (ground penetrating radar) to determine slab thickness and to locate
reinforcing steel, if reinforced (conventional slab on ground or reinforced slab on
ground).
o, Take one set of three concrete cores (after GPR to avoid reinforcing steel) for
compressive strength testing per AC! standards and one core for petrographic
examination per ICRI standards. Repair cored holes in accordance with ICRI industry
standards.
o GPR column for vertical reinforcing steel and lateral ties (measuring spacing) for the full
height of that lift. Verify vertical column reinforcing splices,
o Take one VA" diameter maximum 3"-depth core In column (after GPR to avoid
reinforcing steel) for compressive strength testing per ACI standards and petrographic
examination per ICRI standards. Immediately repair cored holes in accordance with ICRI
industry standards.
RE: Miami Beach, Champlain Towers South apartment building collapse, Part 12
Thread 13