Miami Beach, Champlain Towers South apartment building collapse, Part 11 54

[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
Miami Beach, Champlain Towers South apartment building collapse, Part 09
Miami Beach, Champlain Towers South apartment building collapse, Part 10


SF Charlie
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[SFCharlie]

Only columns K11.1, K13.1 and K15 would seem to be subject to enough cyclical loads to suspect fatigue failure.

I'm confused by your column nomenclature, Maybe I'm using the wrong sheet?

SF Charlie
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[IEGeezer]

It looks like you are using Sheet S2 of 14 revised Jan 17, 1980 and titled Basement Level Dimensions. On the bottom left, I see a grid line marked 14.1 and one marked 15, shown as being about 12" apart. I don't see one marked 15.1. I used sheet S2C-1.0 from the Morabito documents dated 4/26/2021 and titled Level 1 Slab Reinforcement and Framing Plan. It was page 11 from the pdf. I uploaded it in my post above on 20 Aug 21 at 03:51.

The distances between grid lines marked in different blueprints don't match, but I haven't found a grid line marked 15.1. The west-most (i.e. bottom of the sheet) 12" by 16" column at the end of the valet and visitor parking area is offset to the north from grid line K. The vertical grid line for that column is not marked on that sheet, but it would be between I and K, but very close to K, so I am calling it K15. I had to measure very carefully, but I believe that column lines up with grid line 15, and not 14.1 (on the Morabito sheet). The sheet you are using shows 12" between 14.1 and 15. The Morabito sheet shows 8" between 14.1 and 15.

There is also an error on the left hand side of the Morabito sheet where 23' is indicated between grid lines 14a and 14.1, but the actual distance shown on the blueprint appears to be 16' 9". Trying to figure out the distances between columns is a nightmare. There are unexplained differences between blueprints. The whole thing is a dog's breakfast.

 

[AusG]

The whole thing is a dog's breakfast

Perhaps, even if this collapse is never solved to everyone's 100% satisfaction, some edicts may emerge forcing existing building owners and regulation authorities to see that their paperwork is in order, and forcing re-surveys where they are not. This is not my field, but I am a little shocked that someone working on this building, pre-collapse even, would have such incomplete incorrect plans to work from.

 

[Jedidad]

I'm wondering if they thought of trying to recover dashcams from any of the vehicles in the above parking and the underground garage. Many dashcams have a "G-sensor" that will activate the camera when certain forces are applied to the vehicle. Even if some of the cars camera image was dark they might could see the time stamp of when it got activated (assuming the time settings were correct when it was setup).

 

[SFCharlie]

I don't see one marked 15.1.

My mistake, I don't see one either. I'm using the 1979 vs. 1980, 'cuase I'm lazy and I had it handy.


SF Charlie
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[SFCharlie]

I'm wondering if they thought of trying to recover dashcams from any of the vehicles

That has been wondered on this thread before. The point is Miami-Dade is still keeping everything very close to their chest, even though there is no chance of seeing a loved one recovered. I think that they think that they might be sued if something came out, but, at some point, they are going to be sued for destroying evidence by allowing it to perish.


SF Charlie
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[SFCharlie]

2. It would explain the lack of a trigger.

I guess I wasn't seeing the forest for the trees, the building for the columns.
Yes, It seems to me the folk on this thread are coming to the conclusion that there was no trigger. To me, that is the scariest outcome, that a forty year old building just fell down...for a salt water environment and lack of proactive maintenance against corrosion...
Sloppy design, construction, inspection nor, regulatory oversight not excluded

SF Charlie
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[MaudSTL]

For those with a WSJ subscription. Behind the Florida Condo Collapse: Rampant Corner-cutting. If anyone could share a copy, that’d be great.

 

[SFCharlie]

Updated power pointy do-da to reflect recent post re columns

SF Charlie
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[Optical98]

Without further video evidence, how are they going to determine the "sequence" of events? They are going to have to rely on survivor statements...what was seen, heard,, smelled and when.

Can they determine which column or slab fell first without visuals?

What other tools are available?

 

[Red Corona]

I don't have a subscription so I just read the top part like you, but it sounds like it's going to be talking about those sample cores drilled in the pool deck which didn't have any waterproofing in them. I think Building Integrity had a video about that linked earlier.

The K13.1 theory does have some merit to it, but to me it still seems like something internal around M9.1 failed first. We don't have any reports from people in the west side hearing things before the pool deck failure, whereas we do have that from 111 and 811. Everyone from the west side survived, so you'd expect them to have said something.

 

[SFCharlie]

For those with a WSJ subscription. Behind the Florida Condo Collapse: Rampant Corner-cutting. If anyone could share a copy, that’d be great.

If you don't already have a subscription, I find it worth it for the images (their photo editor has an excellent eye!) and the graphic animations Behind the Florida Condo Collapse: Rampant Corner-cutting.
I have included some quotes from the text as an attachment.


SF Charlie
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[SFCharlie]

Without further video evidence, how are they going to determine the "sequence" of events?

... depends on who they is...
NIST had documented every step to the deconstruction of the aftermath with video, drone, and photography.
They have requested that everyone send any video to their web storage.
But we only get to see what they want us to see when they want us to see it, which will be after they have decided what happened, and will probably only support their version of the story

SF Charlie
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[SFCharlie]

so I just read the top part...

...to me it still seems like something internal around M9.1 failed first

For more from the text see the attachment above.
M9.1 Located:

SF Charlie
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[Optical98]

My background is in commercial property mgmt, and resort mgmt on the west coast of Florida. I've also served on several boards and HOAs (houses not condos). I'm assuming the "they" would be Forensic Engineers with some other specialists sprinkled in. But yeah, without more info/evidence, I think this thread has dissected and evaluated as much as We can. Hopefully there will be further drops or leaks of info. Once the courts take over, they might be able to enforce more disclosure.

 

[Demented]

Without further video evidence, how are they going to determine the "sequence" of events? They are going to have to rely on survivor statements...what was seen, heard,, smelled and when.

Can they determine which column or slab fell first without visuals?

What other tools are available?

Thankfully they should be able to do a complete 3D rendering of everything found in the rubble exactly where it laid. There's enough drone footage and geo/laser tracking for them to easily be able to do that for much of the pile. Paired with destructive and non-destructive testing, they'll be able to get an idea of the strengths of everything in place. Scars on building materials will also likely be closely examined. You can usually tell new from old damage, impact vs shear, etc.

They'll be able to, for the most part, put the broken pieces back together. A fine tuned theory of the sequence and causes, but no real determinate answer is what we'll see, I feel.

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

 

[gonefishing2]

but no real determinate answer is what we'll see

I think a water to sand ratio similar to this Demented Image Find........

 

[Demented]

I think a water to sand ratio similar to this Demented Image Find........ponder

Oh we'll definitely get answers to that craziness with this crew. We'll learn about the rebar placement too I hope.

Again, this isn't Champlain Towers South, but still an ocean front condo, same PE stamp, same contractor, same crew, same inspection processes, etc etc. The photos of CTS are like the anti-corrosion coating.

*shrugs*
It's not like work of this high of quality was done on structural beams, the pool deck/parking garage ceiling, columns, or balconies/interior slab...

Water weight on that deck is gunna be so hard to prove. It's been months and it still hasn't rained as much as it did that month, and week in particular.

 

[IEGeezer]

https://www.youtube.com/watch?v=k792KFoYOSQ&list=RDCMUC9xpl8LyFRsKXASGHBBj_xQ&index=1

I just watched this video by Building Integrity about "delamination" leading to the pencil head columns observed after the punching shear. He also pointed out how the cores were fractured.

How prevalent were concrete pumpers in 1980s Miami? When you are mixing on site, you may run out of time doing a large slab. In that case, did they pour the bottom half first and then come back the next day to finish the pour? Could that have led to "delamination?" Just a thought.

 

[Demented]

Yes, I believe there were instances of that.

The 1992-1997 and 2003-2009 (this was a long project with firm/contractor changes) concrete renovation to the pool deck is a lot of the major delamination we saw. Large portions, especially under and around planters, had full or partial depth repair work. There was about 14,000sqft total of repair work done to the top and bottom of the pool deck/parking roof slab. This is also where the failures in waterproofing and rebar placement seem to come from, rather than the initial construction. At least in regards to initial images that sparked the "where's the rebar" question in the first place.

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