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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[SFCharlie]

24-27 - It collapsed upwards slightly if you believe these are true frames of the building.

This is why each frame must be registered The smartphone, whatever was moving around quite a bit.


SF Charlie
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[SFCharlie]

As a reminder, closest-to-original public source of the video is at:

How can I download a twitter video?


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[Santos81]

They'd perhaps be synchronous unlike in the video, and much shorter than electric sparks. A typical xenon flash is 5 microseconds. (One can be seen on exposed 13th floor passageway - two strobes, a few seconds, another two strobes, each strobe occupying exactly 2 frames.) A typical arc/induction spark is ~10 milliseconds and the were 12 tubes going east from each meter room. A single exposure at 30 fps naturally maxes at 33ms.

The strobe heads are located both interior and exterior at every non ground level exit. One of the interior fixtures in the UPH corridor is visible momentarily before disappearing. The units flash at a rate of 1FPS for 4 cycles, pause for 5 seconds, then repeat with asynchronous flashing alternating between each floor. Now add in more asynchronous flashing from circuit delay along with the different frame rates it was played back on the front desk display, the device used to record the playback, which was then uploaded for distribution, and viewed at every display frame rate, it’s going to look strange.

Look back and note I did not state that there are ONLY reflections. A small number of interior lights are visible and an even smaller number of exterior light sources of other origin are visible on some balconies.

The Surveillance system at 87 Park captured the entire event from multiple locations at 60fps/4K. It has continuous recording but will not play back at that quality at the Lobby console nor without action event queue markers.

 

[Jedidad]

Any ideas on how long it might take NIST to finish their report? Do they ever release any kind of preliminary report before a final one?

 

[Nukeman948]

When I play the video I see some flashes that look, to this electricians eye, like arc flashes, a couple that look like the lights were on in that condo unit, even one that looks like a cell phone light for just a second in the last section to fall. I can't see that any of these lights prove anything one way or another. But there were a whole lot of flashes that could line up perfectly with the full moon that was out that night reflecting off the window panes as they fall. That just makes it that much harder to attribute the flashes on such poor quality video to anything meaningful.
Link

Que the tidal forces wingnut theories...

 

[12345abc6ttyui67]

 

[Demented]

@Red Corona
"Alternatively, the failure causes a redistribution of load which affects M9.1 and causes the M9.1-M11.1 beam to detach from M9.1. This then puts the plaza slab into overstress and starts the plaza failure, without anything falling."

I believe this is what happened rather than debris falling to the deck. There doesn't seem to be any evidence of it really. If the roof collapsed anywhere, that slab centered under E2.1, H2.1, E4, and H4 is likely the most suspect place with the work cenetered around it to avoid shoring.





Anyway, I forgot who mentioned it, perhaps Santos81, but they posed a good question.
Why is a building with a 35 year life-limit being allowed to continue occupied in such condition, with such bandaid work done? How do we get regulations or anything changed to stop stuff like this from happening? The white hard hats with the clipboards don't seem to care. I witnessed a roof slab being poured in the rain yesterday.
I do my damndest to blow the whistle on job sites and in shobs when it comes to work like this, however shutup and do as your told.

 

[nessman]

The Surveillance system at 87 Park captured the entire event from multiple locations at 60fps/4K. It has continuous recording but will not play back at that quality at the Lobby console nor without action event queue markers.

You know this for sure?

 

[Auri]

Missing/disorganized building records at a commercial storage facility rented to former Surfside inspector... the plot thickens

https://archive.ph/kdVy7

 

[Demented]

Auri, is it related to this?

They released this a few days ago, alone. I thought that was odd.

Not implicating McGuinness, but odd email to release.
Edit: to release on it's own as the email file, not a PDF.

FOIA request issues makes sense now.

 

[Optical98]

Ohh yesss...the trickling of bread crumbs...I did mention this would happen ^^

Thank you Auri!

When I was tracking the Units and their Occupants, I found that
Maricela P Prieto was listed as the owner of Unit 1111,
she was not the occupant, Gloria Machado was and sadly passed in the collapse.

These are public records. I wonder if Maricela is any relation to Ross?

 

[Auri]

I wonder if Maricela is any relation to Ross?

Probably not; Prieto is a common Spanish surname. The owner of the adjacent unit 1112 is better known, though. Annette Goldstein, former board member ca. 2019, daughter of builder Nathan Goldlist ... Nathan Reiber and the Goldlists met up in Canada.

 

[Debirlfan]

Odd. None of the photos work anymore.

Probably deleted because property is listed as being off the market. It's interesting that the unit was for sale.

 

[Demented]

https://www.miamiherald.com/news/local/community/miami-dade/miami-beach/article253113213.html

https://www.enr.com/articles/52171-...suspect-poor-maintenance-in-surfside-collapse

"Working with the Rapid Response Research Facility of the National Science Foundation’s Natural Hazards Engineering Research Infrastructure Program, NIST has installed accelerometers to measure building vibrations and a seismometer to measure ground vibrations at the 12-story Champlain Towers North condominium, which is a near twin of the south tower. The data will be used to validate computer modeling of Champlain Towers South, says NIST, not to evaluate the condition of the north tower."

 

[Santos81]

Images…

Well done. Nearly 100% accurate.

I believe this is what happened rather than debris falling to the deck. There doesn't seem to be any evidence of it really. If the roof collapsed anywhere, that slab centered under E2.1, H2.1, E4, and H4 is likely the most suspect place with the work cenetered around it to avoid shoring.

The cooling tower and support assemblies didn’t begin to move until after the 2nd collapse portion fell. If you look at the Surveillance video frame by frame, it’s path and sequence is completely visible. It ultimately falls to its final position just before the 3rd section falls and the dust cloud obscures the view.

When the skin is peeled away, things look a bit different and remove the roof first theories from the list of suspects.

 

[Demented]

I can't see anything clear enough in the video frame by frame.
I also fail to see how removing the skin removes that theory entirely. Help me understand. If tower didn't fall, sweet. Let's check that one off as a nope.

If the slab below the support structure fails, but the tower remains is still a possibility. This questionable work in that area involves some questionable work to avoid shoring the slabs for 3 floors. We shores floors to support them to prevent collapse, yes? Lets say we come up with a gimmicky way to remove a beam for a full beam replacement. What we're gunna do is carry up sections of beam, and then bolt them together. Tap into one of the A/C units and run a little transformer welder to stick some shit on. It's bolted, doesn't need to penetrate 100%. We'll weld some small sections of beam to the sides of it next to the support, drill some holes and bolt this thing right on down to the column. Now we weld this beam to the cooling tower. Job done, awesome.

Now, balcony repair company comes along and removes the beam, but uh-oh, this weird bolted together weldment with some only 8 3/4" by 5" Hilti bolts that bolts it down to the columns sags.

They didn't call in a crane to lift it.
They didn't shore 3 floors down to support jacking the beam and tower back up.
This work also got done rush rush and given the stamp of approval even though the field inspector/SI was not witness to the pouring or completion, but somehow the steel beam was back up supported under a concrete beam with minimal cure time. Something weird went on.

Edit: But then again, this was the same crew that shored the x11 and x12 stacks straight down to on top of the pool deck. Smart crew this one was. Multiple days reported they didn't even have work plans or shoring plans on site.
Why can a SE design something and a company be allowed to go around the SE's design/plans and hire a new PE to quickly sketch up a "let not have to go into people's unit's" shortcut? Craziness. It's almost like this was done on purpose to hide it from the SI, who was one of the engineers of the original consulting form overseeing the concrete restoration work.

 

[Santos81]

I can't see anything clear enough in the video frame by frame.

I also fail to see how removing the skin removes that theory entirely. Help me understand

I’ll put together a 3D PDF, with some FEA model examples. But to be brief, the available alternative load paths based on the framing layout and debris field doesn’t jive with a top down modus of failure.

 

[SFCharlie]

Any ideas on how long it might take .... Do they ever release any kind of preliminary report

It has been claimed that like NTSB, NIST will take a year or two for the full report, but also like NTSB, they will release a preliminary report in less that a couple of months, that will only contain matters of fact, but no analysis. (They claim)


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[MaudSTL]

The 'construction' sounds 111 heard could have been small chunks falling, and the 'collapsing wall' could have been a larger piece which caused the failure of the deck.

Both are unlikely to have occurred in the garage as none of the people who used it from 11:00 to 1:15 have reported driving over small or large chunks of concrete.

 

[Nukeman948]

Tap into one of the A/C units and run a little transformer welder to stick some shit on. It's bolted, doesn't need to penetrate 100%.

You don't seem to have much respect for other peoples work. Why is that?

There was 400 amps @ 208v 3 phase power available at that location that could have easily fed a bank of 50 tig welding machines.
You have no proof of your claims. Give it a rest.