Miami Beach, Champlain Towers South apartment building collapse, Part 08 20

[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

SF Charlie
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[MaudSTL]

Source for that quote?

Sara Nir went to the lobby at 1:14. She told CNN (go to 1:45 in this video) that when she got to the lobby, she asked the security guard if she (Sara refers to Shamoka as “he”) had heard that noise. She says the guard told her she had heard it.

 

[Eufalconimorph]

22 Jul 21 16:42
Eufalconimorph with the Gigapixel software...

Maybe you could use that software on the "mystery of what's beyond the Gated Ramp" photo? Prob best to start with an original photo vs anything we can link on here, or just a few posts above this one, Sym P linked one. I'd love to see what you could do with that!

I could. But as I noted in the previous post where I used it, it's a machine-learning system that paints in whatever hallucinations it has when scaling the image. You inherently can't get extra detail when zooming in on something, you just get artifacts. They can be nice, pretty, believable artifacts (like what Gigapixel creates) or they can be blurry junk (like a bilinear interpretation). Anything other than nearest-neighbour interpolation adds false detail. Wikipedia's comparison of image scaling algorithms is worth looking at. Note the details in the algorithm output that aren't there in the original.

"Enhancing" images like this is good for trolling and conspiracy theorizing. It's quite nice for artistic uses. It's utterly useless for engineering analysis.

 

[Spartan5]

No one has interviewed Shamoka Furman, the security guard who was in the lobby next to the surface car park. We know she heard the “collapsed wall” of the first collapse

Per the CNN interview you shared:

We don’t know that Furman heard a “collapsed wall.”

We do know that Nir asked Furman if they heard “that sound” and Nir said Furman replied that they heard “that noise.”

 

[zebraso]

These two cars can be seen in this picture... they are in the guest parking in marked spots.

That photo has to be from after the second half of the building was demo'd. I think that must be understood by most. But it does seem to point out how it clouds the issue of investigation. It did not fall entirely within its footprint.

 

[MarkBoB2]

Spartan5 said:

As others have told you repeatedly, red paint denotes the presence or potential for human remains. Most likely that a cadaver dog had hit on this area of the pile.
None of your the items identified through your theoretical squinting have visible paint on them.

You have not answered my question. If the red paint denotes the presence or potential for human remains, then why has the recovery crew left this pile in place for two days when they have removed the debris around all other 94+ cases of human remains? Is it possible that red paint denotes something else in addition to human remains? Like perhaps some object of extreme importance?

 

[Sym P. le]

... utterly useless for engineering analysis.

If someone gives you photographic or video evidence of a situation and says "This is what I saw", why on earth would it be dismissed. That would be like saying what you saw didn't happen, don't trouble us with your worries. Of course the trolls are out but that doesn't minimize the value of the evidence.

 

[MaudSTL]

Per the CNN interview you shared:

We don’t know that Furman heard a “collapsed wall.”

We do know that Nir asked Furman if they heard “that sound” and Nir said Furman replied that they heard “that noise.”

The reason “collapsed wall” is in quotes is because that is what Sarah Nir has called the noise she heard from above at 1:10 am (which is the same as what Gabe Nir has called the first of three stages of collapse). It is in quotes to indicate that “collapsed wall” represents the words of a witness, in this case Sara Nir. No, we don’t know that it was an actual collapsed wall. It is what the first collapse sounded like at the time to to the surviving witness Sara Nir.

 

[Spartan5]

You have not answered my question. If the red paint denotes the presence or potential for human remains, then why has the recovery crew left this pile in place for two days when they have removed the debris around all other 94+ cases of human remains? Is it possible that red paint denotes something else in addition to human remains? Like perhaps some object of extreme importance?

We haven’t established any kind of timeline for when the red paint appeared or when the pile was removed. Just because you don’t like my answer doesn’t mean I haven’t given you one.

They marked everything of importance with blue paint. If there was something of “extreme importance” wouldn’t that warrant something more than simply switching up the colors? Crime scene tape, cones, a physical barrier of some sort? And then why would they switch to the same color that they used to denote human remains? Why not yellow?

 

[tmwaits1]

This is a good question to ask from the laypersons perspective so I will try and answer it based on my experience in design analysis and inspection of reinf conc structures for almost 30 years. The problem with a scenario where there is no trigger as you describe where the plaza deck has deteriorated and suddenly goes from stable to complete failure in less than about hour is this. Reinforced concrete almost never fails in this short of time without obvious signs of structural distress days, weeks months or years before the actual failure. In fact this is baked into the way reinforced concrete is designed such that failure is not brittle but gradual/ductile so that action can be taken prior to catastrophic collapse. Practically speaking, if there was no trigger then the slab should have shown more signs of deterioration like chunks of spalled concrete on the floor of the parking garage and heavy, noticeable cracking of the slab and beams well before the night of the collapse. The area where the failure occurred seems like a heavily trafficked, well lit part of the parking garage so you would think that problems in this area would have been noticed even by someone with zero knowledge of structures. I'm not saying it couldn't have collapsed without some trigger, nor that the slab wasn't underdesigned and deteriorated, but the evidence makes me lean more towards a trigger of some sort.

 

[MarkBoB2]

Spartan5 said:

If there was something of “extreme importance” wouldn’t that warrant something more than simply switching up the colors? Crime scene tape, cones, a physical barrier of some sort?

They did have a physical barrier of some sort. See the three red cones on the ramp in the attached photo? They are on the only path that can be easily used to reach the pile of interest. The other path is a ramp by the pool that is used by machinery and is easily controlled. And other photos show a red tape between the red cones.

 

[Spartan5]

The reason “collapsed wall” is in quotes is because that is what Sarah Nir has called the noise she heard from above at 1:10 am (which is the same as what Gabe Nir has called the first of three stages of collapse). It is in quotes to indicate that “collapsed wall” represents the words of a witness, in this case Sara Nir. No, we don’t know that it was an actual collapsed wall. It is what the first collapse sounded like at the time to to the surviving witness Sara Nir.

You can’t take that and turn it into, ‘we know Furman heard a collapsing wall.’

As I pointed out in the last thread, in the very CNN interview you are referencing, Nir refers to the wall collapse as “construction” noises and goes to complain about it not because she’s worried about the building, but because she’s annoyed that it’s happening at 1 am.

Now you’ve turned that into “we know two people hearing a wall collapse.”

You are doing the same thing you are aware is an issue and are critical of:

Many media outlets are paraphrasing the source interviews and we should interpret all of these secondary pieces, not just the NY Post, with a grain of salt.

It’s been pretty clear that when Nir went to complain she was more annoyed that the noises were happening at that hour than she was that some portion of the building collapsed. That is, until she went to the lobby and saw it happening firsthand.

 

[SwinnyGG]

If someone gives you photographic or video evidence of a situation and says "This is what I saw", why on earth would it be dismissed. That would be like saying what you saw didn't happen, don't trouble us with your worries. Of course the trolls are out but that doesn't minimize the value of the evidence.

I don't believe he's saying that the enhanced photos aren't valuable.. he's reminding anyone who reads this thread that any photos which have been digitally enhanced represent conjecture, not absolute fact. That's an important distinction and I agree.

They did have a physical barrier of some sort. See the three red cones on the ramp in the attached photo? They are on the only path that can be easily used to reach the pile of interest. The other path is a ramp by the pool that is used by machinery and is easily controlled. And other photos show a red tape between the red cones.

If that 'barrier' existed to keep equipment from operating near that particular pile, there would be another barrier on the other side directly between the equipment operating on that side and that pile.

The simple answer, which he's repeated, is that we don't (can't) know why that pile is sitting there. We can, however, surmise certain things about how it appears in the photo. Namely, I can guarantee you that if something 'of interest' was found, they would not mark it with the same color they had been previously using to mark human remains. Procedures for crews working in these situations are extremely regimented.

It's also, in my opinion, VERY unlikely that this entire situation is going to be resolved because someone finds one little piece of bent rebar, or whatever. This failure, as far as we know today, was the result of systemic failures across the entire lifespan of the building from the initial design phase through construction, maintenance, and monitoring right up until the collapse.

In any event, I'm not sure what your intent is in continuing to belabor this point, but your posts appear to have a definite conspiratorial bent. I'm not sure why that is, but I think you're focusing on one tree rather than the forest.

 

[Spartan5]

They did have a physical barrier of some sort. See the three red cones on the ramp in the attached photo? They are on the only path that can be easily used to reach the pile of interest. The other path is a ramp by the pool that is used by machinery and is easily controlled. And other photos show a red tape between the red cones.

Those two cones spaced 20’ apart are the barrier? There are none in this picture which shows clear unimpeded access to the area.

You also didn’t answer my question about why they didn’t use a different color paint if it was something other than human remains.

Maybe there is something important there. But I don’t thinks it’s davits, scaffolding, Sasquatch, ac units, rooftop ventilation fans, tar paper, UAV debris, roof anchors, etc.

 

[Reverse_Bias]

This is a good question to ask from the laypersons perspective so I will try and answer it based on my experience in design analysis and inspection of reinf conc structures for almost 30 years. The problem with a scenario where there is no trigger as you describe where the plaza deck has deteriorated and suddenly goes from stable to complete failure in less than about hour is this. Reinforced concrete almost never fails in this short of time without obvious signs of structural distress days, weeks months or years before the actual failure. In fact this is baked into the way reinforced concrete is designed such that failure is not brittle but gradual/ductile so that action can be taken prior to catastrophic collapse. Practically speaking, if there was no trigger then the slab should have shown more signs of deterioration like chunks of spalled concrete on the floor of the parking garage and heavy, noticeable cracking of the slab and beams well before the night of the collapse. The area where the failure occurred seems like a heavily trafficked, well lit part of the parking garage so you would think that problems in this area would have been noticed even by someone with zero knowledge of structures. I'm not saying it couldn't have collapsed without some trigger, nor that the slab wasn't underdesigned and deteriorated, but the evidence makes me lean more towards a trigger of some sort.

I would have expected a lot of concrete to falling into the garage in the months before the failure also. A Building Integrity video did mention that there was corrigated plastic on the garage ceiling under the planters used as a cheap fix to prevent water from dripping onto cars. The cracks above it could have grown to an alarming size without being visible.

 

[zebraso]

then why has the recovery crew left this pile in place for two days when they have removed the debris around all other 94+ cases of human remains?

Most likely remains were already recovered and counted in 94+. Red paint stays behind. May I note that the location is approx where "teal shirt" appears in the toktok image. No one wants to hear that, I know.

 

[MaudSTL]

Spartan5, let’s go back to what I actually wrote above. I made no claims that a wall collapsed. I wrote, “We know she heard the “collapsed wall” of the first collapse, which brought Sara Nir to the lobby to complain.” In this sentence, “collapsed wall” refers to Sara Nir’s interpretation of what she had heard at 1:10 in quotes in order to make it clear to readers that this was a witness report. Putting those words in quotes is a standard way to say “so-called”, as in “so-called collapsed wall.” It is from this NBC Miami interview:

“So I start to hear knocking sounds on the walls. I was sure that people were hanging pictures, and then it was more intense, and then about 1:10, the wall above me collapsed,” said Sara…”​

Sara Nir also states it sounded like a wall collapsing above in the CNN interview I previously linked to, if you go to 1:00 in the video.) In the CNN interview I previously linked to, at about 1:45 in the video, Sara Nir also reports that Shamoka Furman said she also heard this, right before the garage collapse (which Gabe Nir calls the second stage of the three-stage collapse.)

 

[Optical98]

Eufalconimorph , thank you for explaining how that software works. I hadn't really considered what exactly the AI was doing, and ya that won't help us here.


Spartan and Markbob, regarding Red paint... if it does represent areas where remains were found.

Why are these 3-4 column (former columns) painted red? They are/were under what was the still standing part of the building.

 

[Colostruct]

This is a good question to ask from the laypersons perspective so I will try and answer it based on my experience in design analysis and inspection of reinf conc structures for almost 30 years. The problem with a scenario where there is no trigger as you describe where the plaza deck has deteriorated and suddenly goes from stable to complete failure in less than about hour is this. Reinforced concrete almost never fails in this short of time without obvious signs of structural distress days, weeks months or years before the actual failure. In fact this is baked into the way reinforced concrete is designed such that failure is not brittle but gradual/ductile so that action can be taken prior to catastrophic collapse. Practically speaking, if there was no trigger then the slab should have shown more signs of deterioration like chunks of spalled concrete on the floor of the parking garage and heavy, noticeable cracking of the slab and beams well before the night of the collapse. The area where the failure occurred seems like a heavily trafficked, well lit part of the parking garage so you would think that problems in this area would have been noticed even by someone with zero knowledge of structures. I'm not saying it couldn't have collapsed without some trigger, nor that the slab wasn't underdesigned and deteriorated, but the evidence makes me lean more towards a trigger of some sort.

This is my experience also. I don't design large concrete structures of the type that failed. But, I have observed "failing" concrete decks and retaining walls where degradation of the reinforcing is causing distress.

I have also observed connection failure and can see that those failures can be sudden. In these cases the failures can be traced back to insufficient design or poor construction. They can reach a point of degradation or minor over load where failure can occur suddenly. This is not as common in concrete as it is in steel since the connections are commonly integral to the construction of the individual elements (beam and column reinforcing continuity). But, if this continuity is not provided in the design (such as grossly undersized reinforcing or inadequate development length of reinforcing) I see a potential for sudden failure.

BUT...This structure waited around until the rehab crew shows up and then falls down immediately. This is just too much of a coincidence to me. Something happened to trigger this event IMO.

 

[Red Corona]

It's likely that they left that pile until last because yes, it is where the initial failure debris is likely to be and they wanted to look at it more closely. Even though that stuff had been moved around by the collapse and by the demolition and removal process.

But I'm sorry, I just don't see any of the things in your interpretation in those images.

I would also say that the presence of balcony railings in that rubble pile clearly shows that post-collapse material is mixed in there and so even if there is stuff from the roof, all that shows is that stuff from the roof ended up in the collapse pile, which isn't really a surprise.

@Sym P. le - yes, it's very clear from the 3D that you're looking at the floor (or maybe water right at floor level) as far back as that dark item running horizontally across the frame. It's one of the big mysteries to me, how that thing that looks like a planter box at M11.1 is apparently sitting on the floor, when it must have come from on (or above if you think it's fallen from higher up) the deck. How is it not sitting on 13" of slab and overburden?

 

[CE3527]

Why are these 3-4 column (former columns) painted red?

Best guess, those column rebar dowels were painted red so people don't trip over them.