Miami Beach, Champlain Towers South apartment building collapse, Part 06 131

[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

SF Charlie
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[BKNJ]

SFCharle: "What does it look like to you???"

I didn't really want to say it, but every time I see this picture, it looks like a body splayed out. Torso/shorts are teal green, left arm straight and white, left leg towards us, right leg perpendicular with the knee bend at a 90 degree angle.

I'm sure it's just an over tweaked image that my pattern matching is unable to cope with... but once I saw it, I can't unsee it.

BKNJ

 

[Retrograde]

Well lookie here, KCE is drilling to the ... Penthouse... boom...

If you think that somehow validates your weird theory that roof anchor work caused the penthouse roof to collapse onto the pool deck - think again.

 

[AusG]

Great work. Did you try rotating the camera back as well as sideways? Seems to me the divergence of the falling grains is increasing, IE the fall of grains is trending more toward the lens as well as laterally. Thus the room is tipping back toward the camera - as well as the deformation you have identified.
General comment: I interpret murky pictures for a living (seismic). It is right to try to interpret that garage murk, but I wouldn't be staking a reputation on anything so far.

 

[Murph 9000]

Do you think the city is trying to cover their ass or have they found something pointing to geotechnical issues????

There is always ass covering with something this big, it's the nature of the beast. I think there's also a genuine "how the hell did this happen?" from all levels of government and the public. Part of it is likely considering all the possibilities, particularly because there may be many contributing factors.

There's also the very public statement by the geotechnical professor that 30 years ago it sank 2mm (possibly per year, possibly more, possibly less, possibly insignificant, possibly significant). If they don't properly study the geotechnical side, questions and doubts will likely remain.

Right now, they are very likely in abundance of caution mode.

Probably a stretch, but I'd be curious to hear real engineers' thoughts on what's happening in this video. How is the structure twisting and deforming to cause what we see in the Ring video?

Excellent work on the images.

It's not my field of expertise, but the only way I can make sense of the 711 video is M9.1 failing as the last step before major failure in the tower. The SE corner of that room appears to slowly drop maybe 5 feet relative to the rest of it; that can only happen if M9.1 is basically gone somewhere below it, and the basement makes the most sense when we see the video from the north and factor in the heavy step slab/beam hanging off it. The loads initially redistribute onto adjacent columns, but they soon overload or fail due to the pull from the twisting and sagging slab. The next column to fail overwhelms the structure and the rapid collapse begins. I'd guess L9.1 next, possibly K9.1 simultaneous to that, as they are also dealing with the patio step-slab failure. The failure of M9.1 was probably due to the abnormal loading and damage done to it as the patio failed.

 

[SFCharlie]

Sometime ago, one of you posted, complaining of no aerial photos since to implosion. I apologize for not remembering who. I've checked Google every day since, and none have appeared. I've also read in the news, an item that TPTB are providing extra security "since the collapse is a holy space". I wonder if TPTB are discouraging the press from posting aerials for some similar reason. (I think I may have just abused the word reason).

SF Charlie
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[Auri]

Well lookie here, KCE is drilling to the ... Penthouse... boom...

Kilsheimer is evaluating hunches, and the hunch I think he was talking about in that clip, which I haven't seen discussed here, is that the penthouse addition could have been constructed without adequately modifying what would've been the original roof now turned 13th floor. So there might be slab or column issues, waterproofing where you wouldn't expect any, and numerous other complications I'll leave to the experts to reason through.

And sorry about your roof/roofing materials theory, I've seen no update affecting the chances of that being the trigger. You've seen the blue-green patio chairs previously outside 111, right?

 

[SFCharlie]

I didn't really want to say it

Thanks for clarifying...
I didn't want to say it either, but to me I see a red face to the left, body on it's side...
wasn't sure it wasn't the devil given the horns and all...

SF Charlie
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[zebraso]

A Cat-Racoon Hybrid?

I see. Well the intent was to frame the crop around the teal green colored object. That was first noticed on the second page/part of this ongoing thread and I don't think anyone concluded whether it was teal colored foliage (which btw was the first mention of planters in the basement by association) or - whether there was the idea of it being the green colored tarp covering used for the roof rolls. Neither of those would I expect to be teal in color based on what I think plants look like or the photos of the actual tarps seen on the roof. So unless a cat-racoon hybrid also happens to be teal I think you may be missing the main focus of the image.
And ok I'm being a little coy I admit it. So maybe there is no teal colored object or material at all.

 

[dold]

Seriously, do you truly believe that a single 16" column is under that much compression, that its failure would result in a 12 story building failing?

We pretty much all agree that there was much more going on than just a column failing in isolation.

In my opinion and some others' too, the failure of the pool deck slab had a significant horizontal effect on one/some of the columns at the lobby level.

What about that other illegally demolished building (5775 Collins Ave.) where they were ripping out columns with a dozer? I think it is actually quite enlightening. GRANTED: I don't know exactly how many columns they had ripped out but the point stands. Especially when your (CTS's) diaphragm is only dragging into your (CTS's) 8 ft long shearwall with a couple of #4's. Also note that by all accounts i have seen, these guys were taking out columns 1 by 1 - no explosives.

From [URL unfurl="true"]https://www.youtube.com/watch?v=f4Ty0OzSNz8[/url] around 0:30.
1: notice the column adjacent to the collapsed column is still relatively straight
2: not so straight anymore and we are forming hinges at the slab and also buckling the columns at both locations to the left of the collapsed column
3: observe how much the entire left portion of the building has moved from it's initial position. A few feet at least.

Yes, I believe the loss of a single column can indeed initiate a progressive collapse. Read: Alfred P Murrah (well...two columns in that case), etc.

 

[3DSoftwareDev]

I've also noticed a lot of people claim the falling debris to be from the popcorn ceiling... and I think it's too fine to be popcorn. It looks like powdered concrete to me.

To my eye, these are smaller, lighter, more bouncy, and more consistently-sized debris chunks, which would likely be from drywall versus concrete. I think the units in this building had simple painted drywall ceilings, with no exposed slab, so it's more likely this is debris from a drywall sheet snapping above the camera. I wanted to also point out, the "popcorn ceiling" term is not accurate because these ceilings, as far as I can tell, were finished with smooth, painted drywall, not the textured/dimensional stuff you might find in cheap or outdated apartments.

I thought if the camera is backed up to the concrete block wall, that it might be coming from cracks grinding across each other in the concrete block wall. Is if possible the slab has cracked above the camera and this is concrete dust from cracks in the slab moving?

I think the camera is backed up against the glass doors of the unit. Which answers one of rodface's questions:

Can we pinpoint the precise location and direction of this view, on a floorplan? This will help make sense of the perceived distortions

Yes, the unit is the 11 on this plan, on the 7th floor.

The camera is in "Unit C", somewhere just inside of the balcony doors and windows. It's facing north toward the hallway, in the central section that collapsed first.

See this Reddit thread if you haven't already:

https://www.reddit.com/r/Catastroph...m_711_actual_location_ring_camera_footage_is/

The “old” initial frame is a bug that turns out to be a great feature here. Question is, how old is it? Could it be from the last activation (minutes ago, hours ago, why did it activate, loud noises perhaps?), or is it from a few seconds prior?

Great feature/bug indeed. I was very thankful for that first frame - an incredible reference opportunity. I assumed it was from just prior to the first frame, but you're right, that's not proven.

I don’t think air movement is a large factor in dust trajectory but it should not be ruled out, A/C registers puffing due to being crushed/pulled, large objects falling outside camera view

I had thought about HVAC playing a role. The behavior change seems fairly linear, so something would have to start blowing and keep blowing in the same direction consistently. There's also not a lot of turbulence in the falling of the particles.

Timing of video end coincides with loss of power but there are delays due to latency in wifi connection, server-side activity. Just some disorganized thoughts on the element of time with regards to the footage.

Yes, I've wondered what else this little heroic camera would have caught if it had kept transmitting data until the room was pancaked. I think we're missing maybe a second of the room's final moments.

IE the fall of grains is trending more toward the lens as well as laterally. Thus the room is tipping back toward the camera - as well as the deformation you have identified.

Yes, it seems to me the room is also falling backwards, which would be consistent with the initial frames of the exterior surveillance footage, where the facade is falling first.

Depending on how much movement is actually happening here, I am surprised that there's such a small, localized area of visible debris from the ceiling. I don't see any other failures in the room causing debris in this video. On the floor however, I suspect the floor slab is hinging causing the refrigerator to raise up and tilt to the north.

 

[warrenslo]

Well lookie here:

Link

 

[warrenslo]

And sorry about your roof/roofing materials theory, I've seen no update affecting the chances of that being the trigger. You've seen the blue-green patio chairs previously outside 111, right?

No need to be sorry. Basically, all the evidence against roof anchor theory has been BS, for example, in yours, there was no blue and only green in Tick Tock. And the green was the EXACT color of the roofing bag left on the remaining building in multiple after-collapse videos.

Also, your "hunch you think he was talking about" we are engineers we don't go off hunches - please provide evidence KCE is looking at this for your reasons. I provided evidence they would look at the penthouse, you haven't. I have provided plenty of evidence that others have further validated, including the city's permit logs. Please provide evidence.

CHANGE MY MIND.

 

[zebraso]

I didn't want to say it either

I mean same here. I don't want to joke about it either if there is the remotest possibility that's what it is. It could be a victim. And I did not process the image to bring out something that was not there. I certainly did not have that intent. The image I copied from I think Yahoo News (ok first questionable thing about it). I doubled the image resolution by resampling with bi-cubic with detail retention intent. Then I did noise reduction and I think level adjustments - maybe automatic and manual, jpeg artifact removal and sharpening and resaved it with the highest jpg quality settings. Of course that in itself is not totally innocuous. But I think it preserved it well enough. The total unknown is the resolution of the phone camera. But I think a safety check is to look at the no parking sign (whatever it says) as you pointed out. You know how big the features are in the lettering. If they cannot be resolved then anything smaller than that in detail must be imaginary. But there aspects of what you see in turns of outlines that are larger that can be discerned straight lines or curves (shapes). So say you thought you saw horns. Nope. I look at it in terms of how many data points have to combine to put something that looks familiar into the right proportions, colors, overall shape and size to fit. You know how hard it is for people to fake photos of people that are pieced from multiple sources to even get it into the right proportion and perspective. You can tell. They almost never get it right. What are the odds of it happening randomly? And rest assured I know nothing about that so I could not do it if I tried.

Edit: I should have done a control. Same source image cropped with no adjusments except luminance levels to bring out the dark areas. And when I say Yahoo News as the source image I mean the tictok image that included the frowny face (whatever) that they published. I enhanced it and cropped it. I did not mean I found the image cropped as such as though someone was sensationalizing this and then I messed with it some more. I was only trying to clarify the "green" actually when I got a bit of a shock. I don't want to even look at it again truth be told.

 

[AutisticBez]

SFCharlie,

Looks like a tired driver of a vehicle slumped over the debris, after crawling out of their vehicle thats just knocked down a column. Please insert thought bubble "opps" near them.

There could be a car under the debris right?

 

[arbitraria]

@zebraso/BKNJ - I was going to make a quick and sloppy overlay of the Philly Phanatic's head, but now I'm feeling incredibly unsettled. I'm trying to make myself feel slightly better by not seeing anything resembling the human form in Electronbelt's enhanced frames. And you would think something so ghastly would be more readily apparent to the woman filming, but it's hard to tell what she could actually see from her vantage point. Then add feeling what must have been sheer horror topped off with a surge of adrenaline...I feel terrible for her and her husband.

Speaking of the aforementioned lightened/brightened frames, does anyone have any additional impressions after looking at them? I feel like the shapes in the foreground of the debris pile are spectacularly delineated, but I'm not sure if that's a genuine or artificial byproduct of the method of enhancement. To me it looks like a beam (too long to be a column?) The segmentation is definitely interesting. And then the background just above it appears to be red in color, but again, how much of that is artifact?

I wonder how close they have been able to get to this actual area as they're excavating, it's hard to tell from the site walkthrough video. And for that matter, how long it will be until any of that information is actually released...for all we know, they have video from inside the garage itself. I'm really hoping they do have a lot of video from a multitude of angles, as has been suggested.

@Rodface - I wholeheartedly agree with you on the Bagster, I thought the same thing on those earlier shots that showed them up close on the roof. Filled quite a few of those over the years, I'm all too familiar.

 

[Auri]

Here's my take on the apt 711 video. Firstly an approx. camera location & orientation:

https://files.engineering.com/getfi...b-9c33-9e62f6cb4ca0&file=711_cam_position.png

A realtor's 360° tour of the unit directly below, 611, is available here for reference, note height/placement of glass doors:

https://www.compass.com/listing/8777-collins-avenue-unit-611-surfside-fl-33154/556451387650155265/

I'll also reference @3DSoftwareDev's excellent sped-up GIF above, 5th post from top of this page, in making these observations:

1. The particle trajectories - falling vs. bouncing - indicate that many are blown or launched from the ceiling not at the very start but as the clip progresses. Gravity is still pointing close to downward even near the end of the clip, see two consecutive frames I've picked out near the end:

https://files.engineering.com/getfi...2-41c5-ac55-328862517f68&file=gravity-end.gif

This means a wind developed above over the course of the recording, pointing east and probably also to the south. The sliding glass doors are immediately south of the camera, and you'd expect them to be closed when occupants are out.

2. While the floor 8 slab appears to be sliding east relative to the floor 7 slab, concrete floor slabs are quite resistant to compression, so either the building's 8th floor slab was buckling/twisting wholesale, or the columns in the L group are sinking relative to columns in M. IMO the latter is far easier to explain, and would be consistent with the observed deviation in gravity near the end of clip.

3. If the columns and thus walls on the left are sinking, for the floor to remain flat, the right side must tend toward an obtuse angle with the wall (seemingly verified by tall dark furniture next to kitchen) and the left side must turn acute. That the "desk" the camera sits on steadily slides to the right could be explained by the wall slowly angling inward and pushing on it.

4. As you know, a square of fixed length will decrease in area as it turns into a parallelogram. Likewise if a wall of columns starts sinking and the floors remain attached, adjacent walls & columns get pulled in and a substantial amount of air must exit. That could explain the northerly breeze. Additionally - and I may be stretching it - what looks like some heavy smoke that creeps along from entrance area across the bar stools near end of clip may be indicative of the hallway columns/walls being pulled southward and forcing debris-laden air into the condo unit - kind of feeding into what might be obvious from other security cam footage, that the north section followed the south section in falling.

 

[Auri]

Basically, all the evidence against roof anchor theory has been BS, for example, in yours, there was no blue and only green in Tick Tock. And the green was the EXACT color of the roofing bag left ...

Those are some strong statements. No blue?!

So I color sampled the original Tiktok video, no enhancements, just plain RGB sampling. Across multiple samples, I could not get a lower blue reading than green. I also sampled the rooftop bag in pic you posted above. It's also got quite some blue. Problem is, it's got even more green, but definitely not green as grass. What's more, the rooftop bag is exposed to daylight spectrum, while the garage debris is likely exposed to fluorescent light. Here is a link to the difference in typical spectrums for daylight vs fluorescent, not ironclad proof, but suggestive that garage lighting would accentuate green over blue.

https://www.comsol.com/blogs/calculating-the-emission-spectra-from-common-light-sources/

Also, your "hunch you think he was talking about" we are engineers we don't go off hunches - please provide evidence KCE is looking at this for your reasons. I provided evidence they would look at the penthouse, you haven't.

Allow me to transcribe parts of the Local10 news video to make this more apparent.

Kilsheimer says at 0:55, "(what) this says to me is the slab was poured as it was gonna be a roof"
Kilsheimer at 1:04, "you might run into waterproofing or roofing, that's a possibility, then we'll decide what we drill in the structural slab below"

Reporter Christina Vazquez at 1:38, "(Kilsheimer) is directing crews to drill into concrete, from a unit's balcony column, and floor"

The whole time the camera pans from Kilsheimer to his crew, who are at unit level, not on the roof, drilling in great weather. What should I infer?

 

[zebraso]

I'm not sure if that's a genuine or artificial byproduct of the method of enhancement.

I think most of the deficiencies in image quality are attributable to the phone video camera. There aren't the commonly seen artifacts from high compression (low res) jpg formats. Now that's probably just from the fact that they were saved and copied for digital media (including) and how they are processed by this web site for display. A lot of factors potentially in the chain. I would hope whoever converted them (re-digitized) from the video frame captures used a non compression format such as TIFF with no compression option. Who knows? But I don't see major artifacts from file format compression. I just see a crappy phone camera trying to take a video under difficult low light conditions. But anyone trying to enhance the images should not in theory make them worse if they know what they are doing. They won't add artifacts per se. But they may unintentionally enhance "features" that were already artifacts in a poor image. So take it with a grain of salt. It's more likely that this web site adds artifacts by the way it resizes the images, but I have no idea how exactly they do it. Every time a jpg is resaved (vs copied) it adds artifacts. In fact jpg is not a good choice for this at all.

 

[LittleInch]

These threads remind me a lot of the Miami Bridge set of posts where in fact most of the issues were found within the first two or three sets before everyone one got a bit fixed on their own particular theories.

A few things have become clear though.

The security video which was there from the start seemed to show instant collapse. It is now clear that whatever first happened, it happened 10 to 15 minutes before the final dramatic collapse. So no - it looks like removal of one column alone did not bring the building down, but started a progressive collapse.

Going back to the Miami bridge collapse, it became clear that the bridge was giving out all sorts of warning signs for days that it was failing, slowly. Now there there was an initiation event (tightening the tendons), but in reality I think the bridge would still have collapsed on its own if left for another week. Same thing here but over a much longer period of inspections and deterioration of the concrete fabric of the building. The previous report recommending urgent work was THREE YEARS AGO. That's a long time for even more corrosion to occur.

There's a high possibility in my mind that this (that bridge would have fallen down eventually all on its own) is what happened here - i.e. for no apparent initiating reason, the pool deck finally failed. Maybe the standing water or planters got a bit full of water, maybe some one tapped the broken column, I don't think we'll ever know.

As for the roof stuff, again was it cause or effect? If the column(s) collapsed, did that initiate a partial collapse and cause things on the roof to fall off or vice versa?

So it would be much better here I think that rather than double up on everyone's pet theory, we stick to real known data ( of which we are almost certainly missing some vital elements not released) and structural issues and how to try and prevent this happening again.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[AusG]

Just to add some fun to the color debate: That yellow sign on the garage gate in the tik tok video? It's not yellow but very dark green with white text. Phone cameras try to make odd lighting look "normal". Enhance that for tiny dim details and you get odd effects back in spades. The true colors of items in these images is not certain at all.