Miami Beach, Champlain Towers South apartment building collapse, Part 12 60

[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
Miami Beach, Champlain Towers South apartment building collapse, Part 10
Miami Beach, Champlain Towers South apartment building collapse, Part 11

SF Charlie
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[AutisticBez]

The ramp is part A of the distance between gate and M11.1

M11.1 is two columns distance from bottom of ramp. Its perhaps nearing 153 feet. Suggesting that the car needs to reach 88 miles per hour to damage a column is incredible.

I am not suggesting the car cleanly blew out the column at freeway speeds. I am saying the car hit the column at maybe 40-50km/h. You know, its late at night, a fee drinks were consumed. An older person is a little bit intoxicated. Old people suck at driving. They are coming down the ramp and the foot taps the wrong peddle.

Impact occurs. Its not enough to instantly destroy the column but its sheared at the bottom a few inches. Rebar at the bottom is broken from rust and the impact. The pool deck was already in a bad state. Somewhere else, another column punching shears, then another. Its a slow progression that maybe takes an hour or more. The sound of this slow progress can be heard in 111 its directly above the area.

M11.1 did not punching shear, because it was damaged before the pool deck collapsed. See, most the punching shear columns remained intact due to the protection the holed deck created. The deck collapsing held the columns pushed through it. M11.1 didn't punching shear, its fallen on its side. Why? The beam at the top prevented it from going through? It buckled, collapsed sideways. Its shear occurred at the bottom. Nobody has a photo of its bottom rebar intact.

In fact there is barely anything left. You think maybe the rebar was brittle as hell? Maybe water had been leaking down it and destroyed it?

 

[Spartan5]

You know, its late at night, a fee drinks were consumed. An older person is a little bit intoxicated. Old people suck at driving. They are coming down the ramp and the foot taps the wrong peddle.

Yikes with the blatant ageism there!

 

[MarkBoB2]

OK, guys, forget for a moment about how the objects might have gotten on the debris pile. The photo below shows the objects on the debris pile that happen to be found found at the same location as the objects in the TikTok video. Therefore, at least some of these objects should be the same objects as the ones in the TikTok video.

The large object immediately behind column 27 (column M10) is the object that SFCharlie noted had only a one foot diameter hole and that I conceded was not an air conditioner. Notice that this object has four mounting feet as I have shown in the annotated version of this same photo below. These four mounting feet suggest the object is associated with some kind of high torque application. Now you tell me what this object is and how it got there. I expect whoever took this photo will have the same difficulty of explaining this object.

Notice that behind this object lies a metal framework with a hole in it that is about twice the diameter of the hole in the first object. This would make it a candidate for the air conditioner that has been discussed at length already. Also notice that to the right of this framework lies what I have identified as a hexagonally-shaped weight on a rod. This object is seen in the TikTok video as shown in the photo below. Also seen on the debris pile as well as in the TikTok video is a metal sprinkler pipe and an object I have called a metal rod in cement. The TikTok video even shows shadows of these latter two objects. Now, you tell me how these objects got there.

 

[SFCharlie]

as I have shown in the annotated version of this same photo

Thanks for annotating the photo.
Might you attach the power point, please?
My aging eyes can't make out what this blog does to photos.


SF Charlie
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[SFCharlie]

I notice it's almost time for a new part. not yet, but soon.

SF Charlie
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[Spartan5]

Thanks for annotating the photo.
Might you attach the power point, please?
My aging eyes can't make out what this blog does to photos.

I’ve enhanced the relevant portions for you:

Part of me feels badly for posting these things given the serious nature of the incident. But the rest of me can’t help but draw attention to some of the craziness that is being taken seriously.

 

[Optical98]

Jeez, that was a hell of a load of laundry... Honestly I have a scratched cornea today, so I can't read the fine print on your pics Markbob :/

Also, if you want clearer pics of the rubble, go to Getty Images and search CTS Collapse pics. Markbob, do that.

 

[MarkBoB2]

Thanks for annotating the photo. Might you attach the power point, please?

SFCharlie, see attachment.

 

[MarkBoB2]

You will have to credit others for identifying the items. I can only claim the creative writing behind the theory.

The poster said (to paraphrase) “yeah I guess that AC unit is only as big as a construction cone as you have pointed out.” They left the rest of their theory that follows ‘hanging’ so to speak. Mine is at least as plausible as theirs.

I’ve enhanced the relevant portions for you:

I was silent from August 21 until September 6, when you resurrected your ridicule of me by re-posting my own previous posts above. Why do you insist on abusing people instead of giving your own theories and defending them? Do you enjoy playing god instead of trying to come up with your own valid engineering solutions?

 

[Spartan5]

Why do you insist on abusing people instead of giving your own theories and defending them? Do you enjoy playing god instead of trying to come up with your own valid engineering solutions?

I apologize if the abuse seems personal but some of this stuff seems pretty bonkers.

I’ve also posted my ideas. Much is awash in this sea of lunacy though. SFCharlie, for instance, missed my posting of the NIST footage which opened, I believe thread 8, because of all of the nonsense about roof anchors and a pallet of 200 tar paper rolls bringing the building down.

Playing god???? In what manner?

Engineering solutions? We haven’t even identified the problem yet.

But I think I found something that matches your sketching. The smoking gun perhaps:

 

[Optical98]

Spartan

I agree with Markbob, this ridicule of others needs to stop.

 

[SFCharlie]

I’ve enhanced the relevant portions for you:

I see an evil monster stomping (raining ?) on other peoples' parades. well... maybe not evil, just frustrated with all the conjecture. At least MarkBoB2 pointed out what he perceives where, not one of those "do you see what I see?" This way we can look at it to see if it makes sense or not.
Thanks MarkBoB2 and thanks for the attached file.




SF Charlie
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[Nukeman948]

Suggesting that the car needs to reach 88 miles per hour to damage a column is incredible.

Well, the comment about 88MPH goes along with 1.21 jiggawatts. It was a movie reference that apparently went over your head.

“I guess you guys aren't ready for that yet. But your kids are gonna love it.”


Back To The Real World...
Some of the posters here are so locked in to their ideas that I'm sure they will never believe the NIST reports when they come out. They will end up as our very own Champlain truthers.

 

[SFCharlie]

Not exactly on thread, but "not the first time this happened"
A Brief History of: The Sampoong Department Store Collapse (Documentary)

SF Charlie
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[Spartan5]

I see an evil monster stomping (raining ?) on other peoples' parades.

If this is the parade grounds, then one dog and pony show is as good as the other.

Maybe this isn’t the parade grounds. I’d be glad to exit stage right if there were another thread that was limited to the posting of new information from reputable sources and other actual engineering information in lieu of all the iSpy, fantastical conjecture, and WAGs we have the last ten threads here.

 

[apper.42]

Do most Engineers behave like 10 year old kids or just most of the ones on this tread right now, why push the same theories repeatedly without adding anything new.

My opinion is that the collapse was precipitated by the deterioration of the concrete in the pool deck. Although no test results from cores have been revealed I believe that the concrete was so weakened by the ingress of chlorides from the environment, lack of proper waterproofing and lack of proper maintenance, that :

1) The slab could no longer act in an elastic manner as designed by the ultimate strength method. Concrete finally failed in compression in a sudden manner instead of the steel failing in an elastic manner allowing redistribution of loads before failure.

2) The severe weakening of the concrete and compression failure led to complete loss of shear strength at the columns where the top of the slab was open and confinement in the bottom of the slab giving most of the shear capacity was completely removed.

Even without a sudden major triggering event the added surcharge DL on the deck due to an added layer of tiles and and waterproofing/sand layer along with any ponding due to excessive rain and lack of drainage of the deck and planters probably contributed. The deck so weakened only required some minor trigger to cause the collapse.

I believe that actual concrete tests will show that the insitu concrete in the deck is about two thirds to three quarters of the specified strength. This is also probably the case for the columns just below the pool deck and just above the parking garage floor.

Poor design, faulty construction and quality control, and lack of proper maintenance all contributed with all of these factors directly or indirectly involving the architect engineers and building officials. Just my humble opinion. Now all of the posters have something to criticize from the structural point of view.

 

[SFCharlie]

If this is the parade grounds, then one dog and pony show is as good as the other.

Agreed
Maybe if I had led with a gentler intro, I would have gotten farther.
I'd be delighted with the posting of new information from reputable sources and other actual engineering information.
Please stick around and bring on your ponies!

SF Charlie
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[Seppe]

Do most Engineers behave like 10 year old kids or just most of the ones on this tread right now, why push the same theories repeatedly without adding anything new.

My opinion is that the collapse was precipitated by the deterioration of the concrete in the pool deck. Although no test results from cores have been revealed I believe that the concrete was so weakened by the ingress of chlorides from the environment, lack of proper waterproofing and lack of proper maintenance, that :

1) The slab could no longer act in an elastic manner as designed by the ultimate strength method. Concrete finally failed in compression in a sudden manner instead of the steel failing in an elastic manner allowing redistribution of loads before failure.

2) The severe weakening of the concrete and compression failure led to complete loss of shear strength at the columns where the top of the slab was open and confinement in the bottom of the slab giving most of the shear capacity was completely removed.

Even without a sudden major triggering event the added surcharge DL on the deck due to an added layer of tiles and and waterproofing/sand layer along with any ponding due to excessive rain and lack of drainage of the deck and planters probably contributed. The deck so weakened only required some minor trigger to cause the collapse.

I believe that actual concrete tests will show that the insitu concrete in the deck is about two thirds to three quarters of the specified strength. This is also probably the case for the columns just below the pool deck and just above the parking garage floor.

Poor design, faulty construction and quality control, and lack of proper maintenance all contributed with all of these factors directly or indirectly involving the architect engineers and building officials. Just my humble opinion. Now all of the posters have something to criticize from the structural point of view

Myself and others have postulated this same general theory, and have presented it across several posts that can be found in the first few threads of this topic:

-questionable design and execution of a highly-sensitive structural system (two-way flat slab susceptible to a punching shear mechanism that is inherently magnified by moment imbalance)

-an unforgiving environmental exposure that pours water and chlorides into the aforementioned structural system

-suspect quality of construction and construction materials

-non-existent periodic assessment/maintenance
.

This boring, vanilla theorizing has long since been buried by what seems like an incessant stream of rubble pile photo-analysis and other sensational musings, some of which I honestly can't believe are even being entertained as legitimate thoughts.

So a sincere thank you for bringing back this plausible/probable logic, despite the fact that it is clearly not spectacular or sinister enough for an increasing number of posters on here.

 

[raymiepo]

Considering 9/11 20th anniversary upon us,……went down a very deep rabbit hole recently.
It is not my intent to highjack this thread - I just have some items I wish to comment.
If anyone objects, I (or would hope, the powers that be) will take down the post.

The other night I watched CNN Films Present: 9/11, the Peabody Award winning documentary that was to be about a New York City Fire Department probationary firefighter but ended up being a minute-by-minute portrayal of the attacks from the perspective of the first responders who answered the call.
I was very moved. Kept thinking of CTS souls.
The doco triggered me into search.
“Falling Man”, photograph taken by AP Press Photographer Richard Drew. Controversial, and drew much criticism and anger.
“Desperation Forced a Horrific Decision” by Dennis Cauchon and Martha Moore, USA Today, Sept. 2, 2002.
I do not provide links here, because I leave the search decision to readers. Not my intent to be ghoulish. The subject matter is personal.

I kept thinking of New York’s Bravest going UP a 44” stairwell saddled with 50 lbs. of equipment and panicked people going DOWN. And some disabled, and some feeble.

“Federal authorities reported that during the designing of the towers, the Port Authority dropped plans to use an earlier building code that would have required six stairways in each tower, and turned for economic reasons to the more lax requirements of a later code that required only three stairways. By building fewer staircases, it could make more of each floor available for rent.”
-NY Times, Sept. 10, 2004

https://www.govinfo.gov/content/pkg...VPUB-C13-8daa429f4f4e901bcd87da64957b40c9.pdf

Chapter 10 > 10.2 REQUIREMENTS FOR A FOURTH STAIRWAY (Pages 159 -160)

https://www.history.com/news/world-trade-center-stairwell-design-9-11

Sadly, learn from mistakes - fire protection for steel, firefighter-communications systems, sprinkler supplies, elevator use…

 

[apper.42]

Myself and others ....

I would encourage others with a different failure mechanism to reiterate their theory here; many have talked about over reinforcement of columns but did it result in failure in a particular way.