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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[Demented]

@Thermopile
So the PH plans, page S10, with BM42 for the cooler support do indeed have it on columns D2.1, D4, E2.1, and E4. It appears as though it was possibly Spanning out from D, over E, and half into the slab between E and H, or just from the E to H lines. Unless I'm an idiot, I can't figure out why the replacement beam called for 24ft for a 14ft 6in span. Probably just most nothing in a sea of messed up prints.

 

[gonefishing2]

Demented, I think As-built the beam spans between E and H which is supposed to be a 23 foot span

The Penthouse corridor changed several times on plans, and they did away with Penthouse Elevator that was in early PH revisions...

 

[Demented]

E to H was 23ft. Only issue I see there is, the entire tower stack should be more East than it is on the PH roof as seen in aerial photos. If they did move it to the E to H span, that makes the janky repair work and modifications even more janky.

4K drone video. Whoooo.

https://youtu.be/VM416Xg-oBQ

 

[gonefishing2]

Here is what I think is latest PH Roof Plan it is S-14A. Look at Shear wall for a reference as to where AC unit is. Also notice it is split 1/2 along PH Corridor wall and 1/2 past end of the corridor wall

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1627175183/tips/PH_Roof_sqayib.pdf[/url]

 

[Murph 9000]

Early plans had the HVAC plant on the D–E span, but that evolved to the wider E–H span. As far as I can see, it was built as E–H, and has remained there since. That's possibly slightly better structurally, as all 4 columns go down to the foundation. D4 goes to a transfer beam on the lobby or second floor slab (I forget which), and is replaced by D5 in the basement.

 

[Optical98]

What is this, where did it fall from?

Edit: Looks like a black steel truss of sorts, but there's no others and we've a flat roof..
Maybe it's a hermetically sealed a/c coil, eh?

 

[Murph 9000]

What is this, where did it fall from?

What is what? I see a bed and bedside table in an 04 unit middle bedroom, and miscellaneous collapse debris. At least describe the object, the position in the photo, and what you're thinking about it. It would also help if you identified which unit in the stack you have zoomed in on.

 

[warrenslo]

The security video shows those floors falling from below, doesn't it?

The upper levels above x10 and x11 are missing in the first frame of the video provided to the public. See earlier post. (The first frame has two blue flashes on upper levels of x10. They appear to me to be electrical.

 

[warrenslo]

The city has withheld any known directly relevant documents to the collapse I believe. Items I've asked for they have not been able to provide.

 

[spsalso]

What I DO see in Optical98's picture is a lack of rebar for about 6' to the left of the bed, after those two paltry pieces.

Is that how it's done?


spsalso

 

[spsalso]

In 1964, an uncle took me to watch them take down a C&O coaling tower in Michigan. They would "wong" it with a steel ball. And then guys would torch cut the rebar. And then they'd do it again. And again. And again.

That coaling tower did NOT want to come down.

I sense a different standard of construction, compared to our current subject.

Wonder why, especially since no one lived in the coaling tower.


spsalso

 

[waross]

The coaling tower was built to own.
The condo was built to sell.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[LionelHutz]

The level of posts in these threads has gone to complete crap. Hardly worth following because it's degenerated into a couple of posters ranting on about their pet theories.

The upper levels above x10 and x11 are missing in the first frame of the video provided to the public. See earlier post. (The first frame has two blue flashes on upper levels of x10. They appear to me to be electrical.

Back at it again. You must think the people that have taken over will accept your theory?

 

[nessman]

The city has withheld any known directly relevant documents to the collapse I believe. Items I've asked for they have not been able to provide.

That's because it's still an active criminal investigation. Patience... in time the facts will come out. But I think we have a fairly good idea of what happened and why.

 

[nessman]

That coaling tower did NOT want to come down.

I sense a different standard of construction, compared to our current subject.

Coaling towers were designed to hold many tons of coal. You still see some standing today because of the costs of demolition. Condos are designed to hold basically itself, some furniture, people and air. As we saw recently, it doesn't take much to bring one down.

 

[MaudSTL]

But I think we have a fairly good idea of what happened and why.

It sounds like this group may be ready to re-cap all the theories on what, how, when, and why. Rather than rehash them all, can we make a list? I will volunteer to rake them off and organize them into a Google Sheet for all to see and refine.

 

[gonefishing2]

I would argue the new folks went to the trouble of joining and posting here because they felt something was missing as far as theories or stringing together the chain of events that led to this disaster.

It would be great to find out it was something really simple and easy to fix so this would never happen again, but after 4 weeks or so of posts, I do not feel that will be the case. Folks have done an amazing job at identifying key vulnerabilities in the structure and provided analysis to explain the weaknesses.

The public has been blacked out of key and validating information due to so called 'crime scene status', thus this is going to probably play out for years in our court systems.

Even Building Integrity's last video post was lacking to me in content. Perhaps we are at the end of the road without sufficient validated data to crank into our models. Also it has been said that there is so much of this building that was not OEM, that it will in all likely hood, be very hard to build those models. Especially after they demolished the key remaining in tack evidence. Look at what appears to be large variations of quality of construction, latent defects or defective maintenance repair work. The materials testing will help get a feel for the general quality perhaps.

Here is a link to Building Integrity's explanation of shear walls. I had hoped he was going to get into the fact that the columns sure looked beefier in the part of the building that was still standing versus the area that had the PH. Why does there appear to be key structural robustness differences in the two parts of the buildings? That is of interest to me, and the effects of such. E.g. The elevated parking fell without taking down the building above it.... It is almost like they built up to the shear wall, then added on beyond the shear wall, but that makes no practical sense. Or designer started designing the remaining part first, but then got pressure from developer to lower costs, so margins were taken out of rest of building, but left in original to save re-design costs? Far fetched but the why the difference is very interesting..

Edit: My memory of the 1979 timeframe was long hand paper calculations with the aid of a hand held calculator, with somewhat programmable calculators being introduced in the 1970's (see second link I found with a quick Duck Duck Go).

https://www.youtube.com/watch?v=2DmPcIzsQtM

https://www.theregister.com/2014/01/03/ten_classic_calcutors/

 

[Optical98]

Thermopile, I agree on his last video, and the analogy of tearing paper if at all should have been torn in a downward motion. The various column sizes are a mystery.

MaudSTL,

This platform makes it difficult to look at gathered evidence (or lacking) of a theory/hypothesis in one place..
Perhaps a spreadsheet would be helpful. How would it be made available for us to examine? Also it can't be up to one person to determine whether evidence gets added or not... Proven Evidence for a theory in one column,
Possible evidence not yet proven in another and then a column for arguments against it?

 

[SFCharlie]

What is this, where did it fall from?

It fell from inside the unit. Entertainment center with 4 screens?


SF Charlie
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