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Miami Beach, Champlain Towers South apartment building collapse, Part 02 151

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dik

Structural
Apr 13, 2001
25,672
thread815-484587


Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
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NOLAscience said:
So a resident of the building was moving a significant number of items to a hotel, just before the collapse. Why? Was the person aware of a problem?

Claimed:

No power in unit on arrival at approx 10:30p - decided to go to a nearby hotel - departed approx 11:30p. Unpacked, returned to CTS at approx 12:30a to leave car, stayed for additional 20-30 min, left by scooter. Returned to site after collapse and stated “my car is in there; now it’s totaled.” Left immediately after.

Plausible, yes. Convincing, not entirely. Timeline and the claimed power outage raises red flags.
 
warrenslo said:
All three of the following accounts depict initial debris coming from above:
1. Mr. Nir, Unit 111: Noises above her unit, knocking grew louder before she heard a "smash," as if a wall had collapsed in the unit above hers. She went to the lobby after hearing these noises. While with the building's security guard in the lobby, and as she complained about the noise, she said, they heard a boom. She ran toward the sound and witnessed the building's underground garage collapse. It was like something out of a movie, she said. Link
2. Ms. Monteagudo, Unit 611: She heard a strange noise and it felt like the building was moving, tried to close the sliding door to the balcony, and it wouldn't close. She then heard a crack, a line in the wall coming down from the ceiling "about two fingers wide" then it started getting wider and wider as she watched.
3. Rosie Santana’s camera, Unit 711: White, hail-like debris coming from above and heard pelting her living room, before the camera abruptly goes dark after 13 seconds. Link

I’m starting to wonder what your game is. You fail to show how any of these three things are indicative of or relate to debris coming off the roof.

1. If debris from the roof were hitting the ground outside of 111 it wouldn’t sound like it were coming from the unit above. And after falling 12 stories it would have to sound a lot louder than annoying construction noises. It would have sounded like it was coming from outside. And they would have rushed to their windows to see what it was.
2. What does a crack in a wall on the inside of the building in a unit located in the middle of the vertical stack have to with anything falling off the roof?
3. The White, hail-like debris coming from above and heard pelting her living room, was a result of the whole building starting to collapse. You can see the huge jolt as the column starts to give 13 seconds before the whole thing comes down. That’s what woke the camera up. What does that debris from the interior wall and ceiling have anything to do with the roof?
 
I apologize to the board for my inflammatory speech, in regards to the "mechanical roof anchors", and OSHA. In my personal experience I have never seen a cast tied in place "eye" for OSHA fall protection. In practice I'am more concerned about (1) the integrity of the parapet, (2) the counterweighting (3) OSHA mandated wear markers, (those colored nylon threads in a ropes for example) (4) making sure that everyone is (a) properly fitted in a harness, and (b)tied off properly. There is a point where you actually have to get on a swing stage to responsibly inspect structures such as this.


 
warrenslo said:
Here's a slightly earlier screen cap, The top 2 floors (possibly 3) are clearly missing over the x11 stack.

Or maybe the entire visible stack of the central structure is in the process of dropping relative to the structure to the left and to the right.

To state with certainty that the top levels are "clearly missing", there needs to be a simultaneous "clear" visual indication that the levels below are still aligned with the levels to the left and to the right. But the video resolution simply isn't high enough to show that.

It would be great if that footage started ten seconds earlier than it does. The fact that it seems to start during the first moments of collapse prevents us from seeing the critical, telling moments that lead up to collapse.

You've vigorously presented your position/theory that work at the roof level precipitated the collapse in the form of large sections of the roof falling down and essentially undercutting the structure at the pool deck level, at which point there is a wholesale collapse. Duly noted. Speaking for myself, I disagree with this theory.
 
I dont understand the fascination with the fall arrest system(s) being installed, even if they were incorrectly installed. There are much bigger problems if a 4 bolt/2 bolt connection into a concrete structure propagates a building failure. These fall arrest systems were not loaded during the collapse. No one was attached to them. No swing stages were currently present. I really think they are a non-factor in this failure.
 
Here's possibly the earliest currently available public video frames of the collapse, on CBS46's channel. It's the same video of a video, but starts with the playback on a blank "No video" screen.


If you watch it in slow motion, the south west quadrant of the penthouse and the penthouse corridor were clearly there, and had not fallen significantly prior to the facade. MAYBE the cantilever section of roof and parapets over the penthouse & 1211 balconies was gone (and the balconies themselves), but it's difficult to be certain, and not in any way conclusive that they fell prior to the facade and main building collapse.

I'm positive the top two levels were mostly still there at the start and fell together with the levels below them. It looks like the floor slabs initially hinged downwards along the row 4 columns and spine corridor. The penthouse corridor holds on for a second or 2, giving a relatively sharp straight line across the top for reference. I'm quite convinced that the main collapse started at IKLM9.1 at patio or basement level. It is possible that the parapet and cantilever roof section fell down onto the patio as an initiating factor, but far from conclusive that they were the smoking gun that started the entire sequence.

The main collapse has already started by the first frame. It's about as frustrating as it could be in terms of evidence for the critical moment.
 
Where did the video of the actual collapses come from?

Strange, that it's the only existing one to date that has been released to the public. It's clearly a cut from the original video file.

And it's been cropped right at the start of the collapse - who did that and why? Where did the video come from? private party? another building? Who provided it? etc...



 
Well, there is a silver lining in most stormy clouds. So far, at least, this is one tragedy that is not yet being blamed on climate change/ donald trump/Boeing QC / the deep state.


"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick
 
There is a difference between the failure of this structure and the FIU pedestrian bridge, or the Hardrock failure. In the case of the FIU pedestrian bridge failure, discrete analysis is appropriate because it was a novel and extremely complex design, in the case of the Hardrock failure it was pure ineptitude.

If you look at the present structure of discussion, in terms of pressure loads over its lifetime, it was extremely well designed and constructed. The building envelope has survived several major hurricanes. In a major Hurricane the differential wind loads are extreme, the pressure gradients in quadrants can conservable be measured at a moment of being at least +/- 100psi per quadrant.

These structures even absent a major wind loaded event are still constantly subjected to blown salt water, so yes corrosion is going to happen no matter how a structure is constructed.

So once again this is entirely a maintence issue, and once again we are a self-regulated industry, the participants in this forum are pretty diverse, and well versed in their individual specialties, and I have read through every post, and find the discourse about how to self-regulate this problem extremely encouraging.

 

You said it... mentioned earlier that this was a 'red herring'...

My earlier post:

"Other than indicating the condition of the structure, or giving you an opportunity to do remedial work, I think the roof anchors are a bit of a 'red herring'... I cannot imagine that the addition of some 5K anchors would have any overall impact on the integrity of the structure. If that sort of load is going to cause problems, then you have a more serious problem at hand. If this had any impact on the collapse, then it was just a matter of time."


Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 

There is one group of scientists that have alluded to this as being a consequence... detracts from the real climate change.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik
 
Kreemerz said:
Where did the video of the actual collapses come from?

It appears to be from a CCTV security camera covering the back yard pool area of the new "87 Park" condo at 8701 Collins Ave. That's just me interpreting the location from the video. Beyond that, I can't say.

The Tiktok one from the north was a hotel guest woken / alerted by the crash of the pre-collapse collapse. Their name is out there somewhere.
 
davefitz said:
Well, there is a silver lining in most stormy clouds. So far, at least, this is one tragedy that is not yet being blamed on climate change/ donald trump/Boeing QC / the deep state.

This guy sure knows how to stir the pot... by the time I'm done typing I bet there will have been 25 replies ahead of me [pc]

I recently designed some critical infrastructure buildings in Miami that were designed for sea level + storm surge in the year 2075. We are talking several feet of projected rise compared to current day. In fact the level was revised a couple times during the design process due to the accelerating nature of the rate of rise! Given the fact that below grade water intrusion was a major chronic problem at the Champlain South building, it's not unreasonable to question if sea level rise + subsidence played a role. I doubt that it did, but it's still a reasonable aspect to consider.

Since Trump's name was invoked, just drive up Collins Ave a few blocks and there is a Trump branded condo high rise, which has it's own structural issues that have been band-aided over: Link. Also similar to Champlain in that it was developed by a corrupt tax evader.
 
NOLAscience said:
there was no load on the anchors last Thursday.

Structural drawings state 25% are to be load tested after installation (5000 lbs)

We do not know if they were load tested for inspection.

5000 lbs on one of those cantilevers, especially the penthouse patio with long spans could have damaged the concrete causing it to fail later.

Someone at a press conference needs to ask the city if the roof anchors were load tested at inspection and if so specifically which locations.
 
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