Miami Beach, Champlain Towers South apartment building collapse, Part 10 79

[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
Miami Beach, Champlain Towers South apartment building collapse, Part 09


SF Charlie
Eng-Tips.com Forum Policies

 

[MarkBoB2]

Below is a close-up of the CTS roof taken on 6/22/21 obtained by zooming in on the aerial photo supplied by Santos81. The brightness has been enhanced to provide greater contrast, but nothing else has been changed.

With the brightness enhanced, by comparing the photo to another photo taken of the same rooftop taken on 1/16/21, one can distinguish that the following things have changed:
1) Several objects have been added to the 88th street side (north side) of the roof by the roofers, including possibly a cache of tarpaper,
2) Two men can be seen bending over the parapet from the 12th floor roof to the penthouse roof on the 88th street side (north side) of the roof. One is on the penthouse roof side of the parapet and one is on a removable ladder on the 12th floor side of the parapet.
3) One of two air conditioning units that were in a row by themselves on the middle part on the south side of the building can be seen to be missing.
4) A bright object that can’t be distinguished is present between the built-in ladder going over the east side parapet wall to the 12th floor roof below and the south side parapet wall over the planter on the patio. This object may be the missing air conditioner awaiting removal either by a crane or by hoisting it over the east parapet wall to where it can be taken through the door on the 12th floor roof to the elevator.
5) A second bright object that can’t be distinguished is present on the 12th floor roof near the base of the stairs going up to the elevator house. This may another air conditioner unit awaiting removal just like the one above.
6) By enhancing the brightness of this photo a second time, one can vaguely see what may be a beam outrigger with counterweights on the penthouse roof going over the south parapet wall over the planter on the patio. With an optional hoist attachment, this outrigger beam can be adapted to lift heavy objects like an air conditioner over the parapet wall, such as over the east side parapet wall to the 12th floor roof below. This is not a verification that such a beam hoist is present. But air conditioners can be removed from the roof only by using a crane or by some kind of roof hoist. So if a crane can be eliminated, a roof hoist can be verified.

It is recommended that readers copy the photo above and paste it into a PowerPoint document, where it can be zoomed in on to help see the objects. To further help readers, I have enclosed a PowerPoint document containing this photo along with ground truth photos from 1/16/21 for comparison. Readers can vary the zoom on the photos in this document to verify how the images were made and improve their ability to discern the objects. A high resolution display will help immensely in such viewing. I have used a 1920x1280 non-interlaced display for such viewing. If one uses a smaller display, like a 640x480 interlaced display, then the photos well likely be blurred beyond recognition. If readers lack a high resolution display, I suggest taking a digital copy of the photo and the PowerPoint document to a Microsoft computer dealer to view them on a good high resolution display.

 

[Auri]

Roof anchor testing to larger loads than specified actually cause more damage FYI.

How so? What's the peak transient force coming from a jackhammer removing old roof material that contacts bare concrete? Wouldn't that force transmit down the whole column? It would seem to me that an anchor test would at most place 5000 lbs of lateral load on the roof slab, even if one of the anchors was planted above a column.

 

[Debirlfan]

6) By enhancing the brightness of this photo a second time, one can vaguely see what may be a beam outrigger with counterweights on the penthouse roof going over the south parapet wall over the planter on the patio. With an optional hoist attachment, this outrigger beam can be adapted to lift heavy objects like an air conditioner over the parapet wall, such as over the east side parapet wall to the 12th floor roof below. This is not a verification that such a beam hoist is present. But air conditioners can be removed from the roof only by using a crane or by some kind of roof hoist. So if a crane can be eliminated, a roof hoist can be verified.

It may be just an artifact of increasing the brightness, but does the edge of the parapet in the area of the possible beam outrigger look straight? It doesn't to me.

 

[Spartan5]

It is recommended that readers copy the photo above and paste it into a PowerPoint document, where it can be zoomed in on to help see the objects. To further help readers, I have enclosed a PowerPoint document containing this photo along with ground truth photos from 1/16/21 for comparison. Readers can vary the zoom on the photos in this document to verify how the images were made and improve their ability to discern the objects. A high resolution display will help immensely in such viewing. I have used a 1920x1280 non-interlaced display for such viewing. If one uses a smaller display, like a 640x480 interlaced display, then the photos well likely be blurred beyond recognition. If readers lack a high resolution display, I suggest taking a digital copy of the photo and the PowerPoint document to a Microsoft computer dealer to view them on a good high resolution display.

That picture is roughly half a mile wide over 2,500 pixels. That translates to each single pixel representing 1 square foot of reality more or less.

And you’re telling us you can discern people on ladders in it???

That’s bonkers.

This smells more and more like some intricate troll but I can’t say that I can understand it.

 

[SFCharlie]

From WPLG Local 10 News:
new-aerial-video-shows-surfside-condo-site-empty
bodycam-footage-shows-initial-surfside-condo-collapse-response

SF Charlie
Eng-Tips.com Forum Policies

 

[Seppe]

Honestly... at this point I'm just here for the MarkBob2 (et al) posts.

My own sanity and the memory of William of Ockham be damned, I'm all in! It's like Tobias Fünke himself is now dabbling in forensic engineering, and I think we can all agree that's awesome.

 

[12345abc6ttyui67]

2000's calling to get their high quality 1920x1280 display back. Can't tell if trolls or not at this point either.

 

[SFCharlie]

It would be really good to see a higher res version of that video ... even just a still of the first couple of frames.

Here is a zip file of the first several frames that show change (no duplicates) if someone would like to sharpen or enhance or process them. Unfortunately recording them from a screen already did some optical processing with may be imposable to undo...


SF Charlie
Eng-Tips.com Forum Policies

 

[Auri]

Maxar provided the image; I realize now where it came from and probably shouldn’t have uploaded it

Not to worry, that image was shared with the press. Sat images were made public 1-2 days after the collapse, only I don't know exactly which days they were taken. I suppose only paying customers get to know that...

There are only a handful of 30-50cm imaging satellites, and depending on commercial demands & cloud cover, it's often many days between successive captures of any given area, and several months between exemplary captures that go onto public sites like Google Maps.

 

[zebraso]

William of Ockham be damned

You are probably correct. This science article attempts to explain why that is. Science mind you.

https://www.theatlantic.com/science/archive/2016/08/occams-razor/495332/

 

[AusG]

For every complex problem there is a simple answer that is wrong...

The trick i think is in not confusing "elegance" which can turn out to be conformance with preconceptions or skipping a few tedious steps, with true simplicity which is using the least number of "ifs".

 

[MaudSTL]

Security Guard Shamoka Furman speaks briefly in this new bodycam video. I wonder if the guy who thought it was a plane may be Justin Willis from the ESPN feature.

https://www.local10.com/news/local/...fside-condo-collapse-response/?outputType=amp

>>>>>Edit: Nah, not Justin Willis, UConn pitcher from 1106. The guy in the video flashes a badge, wears a wedding ring, and says he’s from Penthouse 12. He’s either a member of the Fialkov family or he’s a renter.

>>>>>Edit: The Miami-Herald version on YouTube is different from the local TV version. It includes an approach to the lobby, and a walk to the collapsed surface parking.

https://www.youtube.com/watch?v=BSXm0K_63RI

>>>>>Edit: The NBC News version is also a different version. At the end, this one features the first detailed description we’ve heard of what happened to Shamoka Furman during the collapse. President of the Condo Association Jean Wodnicki (308) also appears briefly.

https://www.nbcnews.com/news/amp/ncna1275869

>>>>>Edit: Radio people are very good at transcription. This piece includes transcriptions of what may have been the master video that the various media cut pieces out of. We now know that Shamoka Furman was the overnight security guard, which explains why residents didn’t know her name or gender. I still want to know who the second shift security guard was, to see if he or she heard the knocking sounds prior to 11 PM.

https://www.connectradio.fm/2021/08...ock-minutes-after-surfside-building-collapse/

>>>>>Edit: This is a better link for the transcription, which is by ABC Audio.

https://digital.abcaudio.com/news/n...hock-minutes-after-surfside-building-collapse

 

[AusG]

Re image interpretation: at high zoom most software smooths things out for you. Turn all that off and you see the pool is at best 20 pixels wide, a floor of the building is three or four. About 0.5m as per Spartan's calculation. Anything smaller is a blur across one or two pixels and objective identification is physically impossible. When you know something is there (eg the roof anchors, the floors) you can clearly spot them. What is happening here is that a pre-xisting mental model is being recognised in the data. In that case the mental models are based on verifiable facts so no problem occurs. In the absence of a verifiable basis for a mental model, minds do their best and recognise suppositions they find reasonable, some more creatively than others. Reasonable only becomes factual though when some other data supports it.

 

[zebraso]

In the absence of a verifiable basis for a mental model, minds do their best and recognise suppositions they find reasonable

That can't be stressed enough IMO. It even applies to witness observations given in a time of high mental stress. Someone said the first story is usually the right one. I don't even think that is true. I mean we see someone that gives the statement to police on the spot that he heard what sounded like a jet *before* the building collapsed from the perspective of a PH unit. I mean first of all is that really an accurate interpretation of what he said. He heard the roar of a "jet" and still had time to escape the PH?
And btw it is not unknown in the history of military aviation for hot-shot "mavericks" to show off their skills to friends and family. They actually had to be prohibited by law. Case in point: my Dad who was a concrete and block mason, witnesses a large crack form in the (unreinforced) basement slab of our home as the result of a sonic boom from one of these cases. He had witnessed that slab being poured about a year earlier. Two decades later my cousin who was an A-6 pilot decided he would take a jaunt over the same property to impress friends and family. There is nothing more to add but that these things have been known to happen.

 

[Optical98]

"The program, known as NextGen, is part of a nationwide initiative by the Federal Aviation Administration to modernize air traffic control from a ground-based radar system to a GPS satellite system that will concentrate planes into highway-like lanes."

https://www.miamiherald.com/news/local/community/miami-dade/article243939867.html

"Under the plan, about 65 percent of flight departures from MIA that previously spread out on parallel paths from Miami Beach to Miami Shores would be diverted to a slender corridor that crosses North Bay Village and moves north over Biscayne Park, North Miami Beach, North Miami and Miami Gardens."

^This program took effect April 22, 2021

I can't find a source to look up flight arrivals and departures the morning of the collapse. Military ops as well.

Could this sudden daily flow of air traffic have an effect on these older structures built on the shifting sands of barrier islands?

https://nextgenrelief.org/media/

 

[zebraso]

Could this sudden daily flow of air traffic have an effect on these older structures built on the shifting sands of barrier islands?

Or to a long neglected structure with highly deteriorated (delaminated) slab? Anyway I assume you are ruling out for the moment any close range supersonic excursions and attendant boom? That could only come from a highly thoughtless and arrogant military jockey who would have in fact not filed a flight plan except in his own head. But I don't think they could get away with it that close to a major airport. I guess it depends. Not likely. The only thing I know is that a P&W j52-p8 in test cell at 110% will make your teeth chatter to the point you cannot stop them. And that's not supersonic. Homestead was rebuilt after Andrew right? I'm not saying it is likely, but.....

Edit: minor typos.

 

[NOLAscience]

New video from just after the collapse, from a policeman's body camera.

https://www.dailymail.co.uk/news/ar...-officers-arrive-scene-Surfside-collapse.html

 

[Optical98]

zebraso

LOL no, not ruling out sonic...supersonic etc. I happen to live near a military base in the Carolinas, and have a cracked glass block window to prove it.

And I said including military ops actually.

 

[NOLAscience]

built on the shifting sands of barrier islands

This is not an accurate statement and could be misleading to readers. This building was built on a solid foundation that was integral with a number of pilings, not on "shifting sands".

 

[zebraso]

I happen to live near a military base in the Carolinas, and have a cracked glass block window to prove it.

I feel for ya, I had to sleep in a BEQ for a while with Harriers flying over it routinely. Talk about nightmares. They were not supposed to fly over the barracks. But they did anyway. That whistling sound that Harriers make.....egads. And now you know where that base is of course. C.P. Half the initial delivery or Harriers is under the pine flats upside down.