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]

I think the movement is blurring all of the x10 and x11 balconies

The thing that's bizarre to me is that there is NO movement for frames 0 - 5


SF Charlie
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[Murph 9000]

The thing that's bizarre to me is that there is NO movement for frames 0 - 5

A possible artifact of a cheap or badly coded motion activated camera system? An artifact of playback starting, throwing up a static image until the playback fully kicks in? That's total guesswork, but the simplest explanations I can think of.

Things have already moved at the start of that video, whether it's just the top or the entire central southern facade. I don't think there can be any doubt that the tower has roughly 1 story missing from that area, we just have different opinions about exactly what is missing / moving at that point.

Also, look at the bedrooms (west side of the units) of 412, 512, 612, 712 (or just the bedrooms from the low level blur up to the obvious 912 balcony). The facade appears quite deformed, as you'd expect from the adjacent x11 living rooms dropping.

 

[Debirlfan]

The biggest problem for the 'roof first' theory (at least the variant of it that has something drop off the roof to start the plaza failure) for me remains the fact that no-one, especially 111, reported anything falling from the roof. If it had bounced off all the balconies on the way down then 611 would have noticed that. We know the plaza failed before the main building, and we know it failed somewhere in front of 111, if not first then certainly early on (from the TikTok video).

Maybe not if something fell from the western end of the parapet. There were only two balconies below, the rest of the floors were double windows. The floors that did have balconies in that location, tennants were either absent or did not survive, so there's no way of knowing what they saw or heard. 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.

 

[253RWD]

Sorry to digress … is there an app for this site? If not, will some one provide a link to the instructions on how to reply directly to someone’s post? Sorry, it’s one of those days. BTW - this is a terrific site. Thanks!!

 

[LionelHutz]

From frames 15 to 17 it also didn't seem to move. To me. the camera was injecting very short pauses into the video. I've seen POE network security cameras do this when viewing the live stream from the camera so the pauses are just not worth any further hand wringing to try and figure out.

 

[SFCharlie]

why we can't see the balconies

I'm trying to corollate what I see in the video with the real building, so I took a couple of snaps in Google Earth Street View

and

I think it is difficult to see the balconies edge on...

SF Charlie
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[MechinNC]

Yea, I think the "pauses" in that frame by frame series are likely not real pauses, but something due to the sampling rate of either of the cameras. Some in the series are likely the same image.

Really grasping at straws with the endless analyzing of very poor video. I know better vid must be out there, but man they are keeping this investigation TIGHT. No leaks that I know about.

I still think I see a red-ish dust cloud early in the collapse vid, which could have come from the patio collapse. Visible down low, partially obscured.

 

[SFCharlie]

instructions on how to reply directly to someone’s post

No app that I know of
Copy the name date and time line from the post you wish to reply to
In the Reply To This Thread box at the bottom of the page, click on the cartoon w/speech bubble
Paste the name date and time line in the query box that pops up, click OK
Write your reply, preview it to make sure you said what you meant. you may need to page down.
When you like what you wrote, click submit


SF Charlie
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[SFCharlie]

Really grasping at straws with the endless analyzing of very poor video.

Yes My intuition was to say it was imposable. But I felt I need to present evidence in the midst of all the bickering. However some times I see lights turning on and off with no downward movement. or I see leaves on the tree in the foreground move in the wind, so no, it is not duplicate frames, but real stops and starts...


SF Charlie
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[SFCharlie]

It has been very hard work copying frames, keeping the numbering straight, registering images to make up for handheld camera work. I'm tired, but here are the first 34 frames.

SF Charlie
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[MechinNC]

SF- Good work, thanks.

I'm still not convinced that some images are not copies of the prior ones. Especially towards the last several frame, once the collapse really gets moving. It's just not rational that the collapse would pause at that velocity.

 

[Eufalconimorph]

It's a video of a screen playing back surveillance footage, taken on a phone or some other camera. Most surveillance cameras will have a 24 or 29.97Hz frame rate, with the latter being common in the US. Most screens have a 60Hz refresh rate. Most phone cameras will be at 30FPS. Having all three frame rates sync up perfectly would take a miracle. So there will be some duplicate or mis-timed frames in any such video.

 

[SFCharlie]

I'm still not convinced that some images are not copies of the prior ones.

Neither am I, but I do see a light come on in frame 9, with no apparent movement, so I don't know...


SF Charlie
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[SFCharlie]

So there will be some duplicate or mis-timed frames in any such video.

Yes! ...bound to be...

SF Charlie
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[nessman]

It's highly likely that the video of the collapse didn't start (at least the one we've all been seeing) until after the collapse began. You can be sure that the camera and NVR system where this recording took place is in the possession of investigators for further analysis.

There is likely video from the camera system at CTS and assuming that the NVR survived - it's in the hands of investigators and nothing's been released yet.

You can also be sure that investigators canvassed every building with a line-of-sight to CTS and is in possession of those videos - and done so as soon as possible after the collapse so they wouldn't lose the recordings due to overwriting of older footage.

 

[LionelHutz]

SFCharlie - that's good work, but I don't see it proving anything.

I think the lights are messing with the camera image quality. Also, in low light cameras tend to blur motion so that could be messing up the image quality as well.

To me, that column without lower level balconies is ending with the 11th floor balcony right above the windows with lights on. Then, there is the strip that is the 11th floor, another strip that is the balcony/parapet at the 12 floor and then the roof parapet. A possible reason the top level parapets aren't as wide as they should appear is because the facade wall is dropping first so the floors has hinged down enough the camera is seeing them from an angle instead of straight on.

To me. all the collapsing floors have already dropped about a floor.

I see nothing that definitely points to part of the roof missing or falling off first. I don't see how any more details can be gleamed from that video based on how crappy that area appears.

I can't make out anything at the left of the collapsing area because of the lights.

I actually saw most of the above just looking at the Youtube video. Scanning these frames just confirmed what I already believed.

I really don't see enough of a difference between these groups of frames to be able to claim the building stopped dropping during these frame groups. From the crappy footage, I would be more inclined to believe it is the camera or the playback device causing these pauses.
08-11
12-15
17-19
20-22
24-27 - It collapsed upwards slightly if you believe these are true frames of the building.
29-32
33-34

Of course, I'm sure others will give long written explanations on how the frames must be different.

There is a reason why the established structural folks on this site have mostly given up on this thread. It's because they don't speculate and chase wild theories and other unrelated crap, not because they can't due to their profession but rather because they know how stupid it is to do so.

I haven't seen very much for postings that would be considered FMEA in the last few threads. FMEA would involve looking at a failure mode and then examining what the result of that failure would be. For example, if a transfer beam failed what could happen. It's not posting on about labor skill or who did what renovations or chasing a white car even though there isn't an ounce of evidence it was involved in any way.

Finally, this isn't a forensic engineering area, it's an area to discuss engineering failures. But, if you want to talk forensic engineering, then there's not much of that going on with the stupid throw the spaghetti at the wall and see what sticks that's happening here. It all happened in the first few threads when the little evidence that was available was first examined and discussed as to it's meaning. This is when the established structural folks mostly stopped posting because they know it's impossible to do any deeper forensic examinations without more evidence and the evidence had dried up. They also know how pointless it is to try and convince the "what if" wild theory crowd that it's pointless to keep at it. Remember the "it was a car hitting a column, end of story case closed" post? Dealing with that level of stupidity drives rational folks away.

 

[Santos81]

However some times I see lights turning on and off with no downward movement.

Most of the “lights” in the x10/11 stacks are reflections from glass that is no longer in place. The two bright flashes from the X10 stack are reflections from a fire alarm signal on the exterior landings of stairwell 1. There are a couple of exceptions but it’s a very macabre subject I don’t feel is appropriate to discuss in detail.

 

[AutisticBez]

Would you really want to watch a high res video of the collapse footage? I mean you'll be watching people die. I think there is at least one person caught on footage in the low quality version.

 

[AusG]

Thank you SFCharlie. Mammoth effort.

 

[Optical98]

SF Charlie,

Regarding the "established structural folks" having given up on this thread bit, nah they're still here with their sock accts....obviously.

This looks to be the most successful thread on this site, and it will probably continue to be until we get real answers and closure to this shocking event.

As more evidence becomes available we'll all be here to analyze and discuss it.

I appreciate your efforts o/