Miami Beach, Champlain Towers South apartment building collapse, Part 13 44

[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
Miami Beach, Champlain Towers South apartment building collapse, Part 11
Miami Beach, Champlain Towers South apartment building collapse, Part 12


SF Charlie
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[MarkBoB2]

If one doesn't have new info, take a closer look at the old... What's Waldo? Please help me identify the lettered objects, Thanks.

While we are asking for help in identifying objects, can anyone help me identify the object in the yellow box in the following photo?

 

[Optical98]

SF Charlie

You know what those items are... item B has been discussed several times.
What is going on here?

MarkBob

Do you have the original, unzoomed pic? I can't tell what direction or when in the clean-up this is.
I might have something clearer if I know where to look.

 

[Nukeman948]

In my attempts to ID stuff in Debris, I made these:

Sorry, I thought you were joking about getting an ID on these things because they have all been identified before.
A. Unknown column or possibly one of the beams that held up D and E Probably a door. (Thanks Optical98).
B. Part of the East shear wall, you can see where the stairs and landings were.
C. Another part of the East shear wall.
D. Steel frame that supported the large A/C. (It's upside down).
E. Large A/C unit. There are plenty of better pictures of it on previous pages and discussion on how it must have tumbled on its way down.
F. Bigfoot.
I didn't bother counting the floors. Some can't be seen because they are in the basement.


Since some people here don't seem to understand my humor, Bigfoot is not real, I just wanted to say F. Bigfoot.

 

[Nukeman948]

...the object in the yellow box in the following photo?

Can't see anything we can identify to get a size reference, but, to the right of it could be an automobile, so it could be a partially obscured scrunched up automobile.

 

[Optical98]

Item A is a board, shelf...drop ceiling tile? It's too clean across the top to be a broken beam or column imo. Maybe a closet door or Bifold?

 

[Nukeman948]

Maybe a closet door or Bifold?

Yes.
A much better photo proves (at least to me) what a waste of time it can be to try to identify items by zooming in on pictures when we know the investigators have already laid hands on those items and found them to be totally unremarkable and irrelevant to explaining how this building failed.

 

[Optical98]

Nukeman

They may have, but from what we're being told they're not going to share anything with us for 4-5 yrs. But there are games being played on here, I agree.

 

[AutisticBez]

SFCharlie,

Isn't B the shearwall to the staircase in the collapsed part of the building? It was connected to the section which fell last, fell off during its collapse, ended up on top? You can see the stair pattern.

 

[SFCharlie]

You know what those items are... item B has been discussed several times.
What is going on here?

Sorry, I did not recognize the shear walls.
The AC looked like cylinder, I don't know why and "A" looked like it was standing vertical when viewed from the SE but I realized what it was when I viewed it from the NE.



SF Charlie
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[MarkBoB2]

Do you have the original, unzoomed pic? I can't tell what direction or when in the clean-up this is.

Thank you, Optical98. Here is an unzoomed photo that you can zoom in on by scrolling in Windows 10:

 

[SFCharlie]

Isn't B the shearwall to the staircase in the collapsed part of the building? It was connected to the section which fell last, fell off during its collapse, ended up on top? You can see the stair pattern.

Yep! Thanks


SF Charlie
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[SFCharlie]

Sorry, I thought you were joking about getting an ID on these things because they have all been identified before.

The shear walls threw me. Thanks


SF Charlie
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[SFCharlie]

Item A is a board, shelf...drop ceiling tile? It's too clean across the top to be a broken beam or column imo. Maybe a closet door or Bifold?

Thanks for the reference photo, yea, but there's a row of somethings across the top (like rebar?, too small?)


SF Charlie
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[SFCharlie]

Do you have the original, unzoomed pic? I can't tell what direction or when in the clean-up this is.
I might have something clearer if I know where to look.

I think this might be what you're looking for...

edit (is this part of the demoed North wing?)(I think the standing column is I14.1)

 

[Js5180]

Hi All,

Not sure if we’ve beat this horse to death yet but just in case we haven’t, the pic posted up above shows some pretty significant damage at the area of the OSHA hooks, circled:

I’m not suggesting there was anything hanging from these, and the slab around them is all present. Nevertheless the amount of damage around these is curious. Why were they a weak spot such that they completely pulled out of the slab?

 

[spsalso]

I see the one at the lower left. On the upper right, I see a sheet metal box.

For the lower left one, I do suspect the the anchoring provided a weak spot to start a crack. When it landed.

It's then a reach to say it CAUSED something.

Are you saying that, except for that OSHA thingy, the roof slab would have fallen and stayed in one piece? Maybe. So?


spsalso

 

[SFCharlie]

RE: MarkBoB2's Photo:
I think the Blue Circle is the Approximate Camera Position?:

SF Charlie
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[apper.42]

Hi All,

Not sure if we’ve beat this horse to death yet

What looks like cracks are rips in the roofing torn off of the slab, this does not mean that the slab cracked in these locations before it fell....the roofing system is ripped, probably due to the impact. I would not read anything into this picture, as is the case for many of the pictures posted here ad nauseam.

 

[TheGreenLama]

I am perhaps misreading this, but it sounds like the corners were "rounded" by the bars passing them as the slab descended.

That is an interesting observation, and one possible explanation. Others could be that it is the angle of the concrete shear cracks, or it could be a by-product of the poor slab concrete.

details of some of the column tops

Here are a few close-ups captured way back in Thread 3, 7 jul 21 1:23

The poor condition of the deck slab concrete is apparent. It's also worth noting the hooks from the column steel. They haven't engaged any deck slab concrete. And in most instances you see the 4 corner bars sticking up. I would have expected at a bare minimum they should have been ripped away by the deck slab steel as the columns punched thru. In fact the deck slab column strip rebar is largely absent from the images. Is this a result of missing rebar, bad concrete, or a combination of both?

Major repairs were slated for some of the column caps. Which ones we can only guess at, as they are not even clearly indicated on the plans (Sheet S2C-1.0, note 10 of the 40 yr restoration [link file:///C:/Users/a/AppData/Local/Temp/8777-collins-avenue---preliminary-review-plans-for-40-year-re-certification.pdf]Link[/url]). But clearly Morabito saw a problem. Was it inadequate original design? Was it punky concrete? Was it missing top slab column strip rebar? Maybe it was all three.

Here's a question for the NIST investigators. Even if all of the deck slab column rebar that was called out on the plans had been provided (4-#5 or 25% of column strip rebar centered over column), would that have prevented the successive punching shear failures, given the (seemingly) poor condition of the deck slab concrete?

 

[SFCharlie]

Here's a question for the NIST investigators. Even if all of the deck slab column rebar that was called out on the plans had been provided (4-#5 or 25% of column strip rebar centered over column), would that have prevented the successive punching shear failures, given the (seemingly) poor condition of the deck slab concrete?

While we wait a few years for NIST, I'm going to ponder the question; if the rebar had been adequately protected from water intrusion, would the deck have failed?

SF Charlie
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