Miami Beach, Champlain Towers South apartment building collapse, Part 09 139

[SFCharlie]

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

SF Charlie
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[NOLAscience]

South African Architect Mike Bell has published a new simulation with narration.

https://youtu.be/2INrz2u9-sQ

For those who won't open up YouTube to watch the video. Btw, you should; it is short, but packed with good visuals. I think this simulation of the collapse agrees well with the security cam video, without the need for a collapse starting at the roof area.

 

[Demented]

@Thermopile,
Sadly no. We have an old clapped out Bridgeport lathe with no dead man's pedal and a Vectra knee mill that is essentially a fancy drill press in this shop. M-I-C, K-E-Y, M-O-U-S-E.
I've done some pretty far out there set-ups to get jobs done with a lack of tooling. The man in charge of the shop is an artist who after cutting it twice and it still being short too many times, has finally learned to cut it 5" to long and trim it to fit the .9:1 print he printed out on the big printer using the surface plate as a work bench.

I gifted my vintage Buzz Box to a new welder a few years ago. That thing got me my start on Al GTAW. Those AC only Buzz Box's still are some of the best transformer welders. After 20 years of dragging it along in moves, enough was enough.

@BadgerPE
Thank you so much.

@Seppe
Pardon me if you think it's all just silly conjecture, watercooler talk, and spaghetti against the wall.
For my crazy ass speculations, as far as I am aware, I've done my very best to disprove more of my own stuff than anything else. Sure, I'd probably be more in my element if this were an exploded or crashed airframe, or a vessel that sunk, but having seen what I've seen due to craftsmanship flaws, at least in my own sense, I know it's not a waste. If anyone thinks any agency that is going to be directly involved in the investigations is NOT going to dive into the past of the building before the collapse to come up with suspect areas to check, you're simply foolish. We cannot simply go "Well, the building fell down because the design would have made it come down if the deck collapsed".

https://www.nist.gov/disaster-failure-studies/data-portal

Why did the remaining structure not collapse? Better question? Well for one, I know there was an absolute ton of jack-leg work done on the ocean side of the building, but the work done along Collin's Ave is vastly different in everything from it seems quality, buiding materials, inspection, and permitting. I'm fairly certain I'm not the only one who can see how sections of the building would not resist collapse or additional stress due to failures of past contractors and poor, or no, engineering to modifications. In an ideal world, we'd hope that one column is not what it takes to bring a building down. But in a world where one column may just be able to bring an entire building down, there is only harm in refusing to look at other contributing factors. I still do not understand how people can model a building off of what we know is, as per a lot of the as built we see, off of simple speculation that nothing out of the ordinary is going on. We know 100% this is no ordinary situation. It's like a rocket surgeon insisting that the Challenger disaster only happened because of a lack of an escape system. Bad analogy, but I know some will understand.

This building wasn't OEM.

I may be insane, but at least I'm not the one insane enough to scribble on a contract/permit for the pool deck to use smooth 305 stainless rods in place of rebar. So you want to talk about the decking that collapsed? I'll gladly jump back to hundreds of tons of added water on the pool with clogged drains and faulty construction. I'll even dig back in for the photos of and emails of complaints of sand and styrofoam clogging drains in the garages and pool decking thanks to changes in Surfside's beach access policies and even issues of dump trucks of sand using portions of the underground ramp to turn around during an ACoE project. I don't have any form of maths on the vehicle weight, but I'm pretty dang sure that's a little overloaded. Anyone ever put any thought into why we see so much upper spalling?

This sort of deviation from standards and plans should not be brushed off as nothing.

There is no doubt in my mind that if people's models were modified to include the known as built vs the as design, that pool deck collapse would be far far easier to happen than any of us all can even grasp.

 

[gonefishing2]

Choose the Right Synonym for badger
Verb
BAIT, BADGER, HECKLE, HECTOR, CHIVY, HOUND mean to harass by efforts to break down. BAIT implies wanton cruelty or delight in persecuting a helpless victim. baited the chained dog BADGER implies pestering so as to drive a person to confusion or frenzy. badgered her father for a car HECKLE implies persistent annoying or belligerent interruptions of a speaker. drunks heckled the stand-up comic HECTOR carries an implication of bullying and domineering. football players hectored by their coach CHIVY suggests persecution by teasing or nagging. chivied the new student mercilessly HOUND implies unrelenting pursuit and harassing. hounded by creditors

 

[Demented]

Hector.

*fingers crossed for a gold star*

 

[JStructsteel]

All that tar paper piled high on the part that DIDNT collapse. Thats the cause right there. Please expand on this theory.

 

[CE3527]

But we can go, the building fell down because the design made it fall down if the deck collapsed.

It may be the "it's just a pool deck" thinking that led to the maintenance not being taking seriously for 40 years. If one of the condo units had cracks, water, and rust dripping into it, they would have jumped all over it. What was likely overlooked by everyone, and not surprisingly since it was unprecedented, was the danger the deck posed to the building.

 

[Demented]

Based off of the emails with the consultants and condo board to the town of Surfside, they were indeed VERY desperate to begin work on the full slab replacement ASAP. They didn't care about costs, they didn't care about time, they only cared about additional parking off property so that construction could start A-FUCKING-SAP. But town officials stalled. It seems in fact they very much wanted to get this done right this time, finally. They've been screwed over by so many bad contractors that it ballooned the prices so astronomically high, I cannot imagine they wanted to risk doing this all again in another 5 years.

This "it's just the pool deck" thinking wasn't their thinking it seems from everything that's been put forth.

 

[spsalso]

While jumping all over the bozos who worked on this building for 40 years is not unreasonable, hold back something for the architect, the engineer, and the general contractor who built it in the first place. Plus a dab for the building department that missed it all, while it was being built right in front of them.


spsalso

 

[Demented]

Unfortunately some of those who have a lot of the blame are already taking their dirt naps. It doesn't stop my outrage at them though. They're just not the only at blame it seems.

Edit: I don't know about other states, but damn man, Florida didn't even ban driving with open containers in your hand until 1988. Construction crews run on 2-stroke. Yuengling-ling-ling-ling-ling-ling
Edit again: Crap, when did this state learn to acnhor roofs down on single family homes? 1992?
Edit: Ever stop at a gas station around 12PM, go inside, and wonder what the guys in the yellow shirts and the beers in their hands do when they go back to work?

*Sings along to Lesley Gore*

 

[Demented]

On a more somber note. All have been identified. 98 confirmed.

https://www.youtube.com/watch?v=1F1JQ1kLtOQ

 

[spsalso]

While the "South African" video is quite good, I also recommend the video that Sym P. le volunteered:

https://www.youtube.com/watch?app=desktop&v=fFQ7ey5CDLc

I thought it had a lot of good comments, while still being understandable by a Sparky. He did good.


spsalso

 

[NOLAscience]

Final missing person identified

https://www.cnbc.com/2021/07/26/flo...-missing-person-identified-death-toll-98.html

 

[Eufalconimorph]

98 is a lot less than 161. That's great news that so many weren't there who might have been.

 

[AutisticBez]

The building might have been poorly designed and built, but it stood for 40 years, and onus of repairing and fixing any issues or faults lay with the owners. There were plenty of signs of problems. There were measures they could have employed to work out if the building was safe.

The default of the building being safe unless things are falling down, seems to the assumption. Perhaps with products, we should be working out "when is the end of life" for a product. 7 years seems to be the best before on plastic parts in the automotive industry.

Is 40 years end of life?

 

[AusG]

The Structural Madness video is pretty good: a detailed analysis indicating the pool deck was on the brink of collapse and that the connection to the building at the step compounded matters. Does not cover later insults to the fabric like the core holes and the delamination but otherwise good I thought.

 

[AusG]

Standing for 40 years is not itself a qualification for standing another 40 if the accumulated flaws and faults over that time played directly into design and construction imperfections that in combination create conditions for a more sudden collapse than engineers' experience leads them to expect. I agree completely that delayed and cosmetics-focussed maintenance was an issue, but if the prevailing wisdom was that a structure in terminal peril will express itself before disaster I can see why human nature took the path of least resistance.

I believe there will need to be a specific inspection regime developed for similar aged/design structures that looks for weaknesses from age and accumulated misuse, and probes critical structural connections for integrity, steel content, etc.
Edited to add: there seems also to be scope for more legislated carrot and stick mechanisms for encouraging owners to undertake heir own structural as opposed to cosmetic inspections and improvements, perhaps by a scheduled depreciation of buildings that do not comply. Good luck with that one though.

 

[lucky555]

How is concrete infinitely repairable? Multiple repairs were hammering out spalled concrete, sandblasting rebar and then fill with concrete and oh look at the lovely cold joint.
I can't see the strength in "repaired" columns.

Original construction contractor Edward L. Nezelek Inc. sure has a track record of shoddy work and so many lawsuits. He seemed to think everything was an extra charge or was a true rat. This (1981) sound familiar, just like Coral Gables?

"Gesco filed suit against Nezelek alleging breach of a condominium construction contract and sought damages for alleged substitution of inferior materials, defective construction and delay in completion. Nezelek denied these charges and asserted several affirmative defenses, among which was a claim that Gesco was solely responsible for the construction delays. Nezelek also counterclaimed to foreclose on its $1,117,614.92 mechanics lien which represented the alleged balance due under the contract..."
"Another dispute concerns damages resulting from defective construction of the condominium's parking deck. Gesco claims that Nezelek's failure to follow its specifications resulted in a leaking deck, and that in addition to the alleged defect in the deck, that this leakage also damaged cars which were parked below the deck. The parking deck was made of concrete. Concrete, as noted by the trial court, is a porous material which will crack and allow water to leak through. Gesco was well aware of this fact. Its own consultants advised waterproofing the deck. Nevertheless, Gesco elected not to do so. Therefore, the fact that the deck did crack, allowing water to leak through, should have come as no surprise to Gesco. Having ignored the warnings of experts as to the consequences of failing to waterproof, Gesco may not now recover the expense it incurred in reconstructing the deck. It is interesting to note that upon this reconstruction, Gesco employed the very waterproofing technique which it rejected initially. Gesco's other allegation concerning premature "shorring" by Nezelek is unsupported by the record. However, the record does contain evidence that Gesco may have contributed to its own injury by using heavy equipment on the deck.
The trial court found, and we agree, that the only defect for which Nezelek was responsible was its failure to waterproof certain planters located on the parking deck. However, contrary to Gesco's assertions otherwise, the record does not show that this failure was a factor in the overall damage to the deck. The court's award of $5,000 to Gesco for corrective work was proper and shall go undisturbed."
Link

 

[spsalso]

I wonder if the condominium owners would have taken the building's condition more seriously if they had known that it was poorly designed and missing rebar. Should they have known that? How? Should the builders have told them? Should the building department that approved the plans and inspected the building have told them?

It seems that the condo people were the only ones who weren't professionally trained to judge the building's condition. I will cut them a lot of slack on trying to puzzle out a way forward.

spsalso

 

[MaudSTL]

For your convenient reference, I compiled the significant witness events we know about into a spreadsheet with links. I wish I could interview some of them to gain more clarity.

 

[AusG]

Outstanding effort!