Miami Beach, Champlain Towers South apartment building collapse, Part 11 54

[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


SF Charlie
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[SFCharlie]

Philadelphia Wedding Dannon and Ryshawn
52 viewsMar 30, 2013
Construction Engineering & Failure Analysis

Construction Engineering & Failure Analysis at his best

or
WTF
or
(I can't find my favorite showing how a stick can bend)

 

[Sym P. le]

I said "MAYBE"!!!

 

[Red Corona]

> You can actually see what looks like deformation in the pool deck in some of the photos. Or maybe it was designed that way for drainage.

I don't think that's deformation, you'd expect to see signs of it against the back wall if the slab had sagged - and although the attachment to that back wall was pretty minimal, it was attached, so that's also the least likely place to see initial deformation.

I think they didn't lay the sand and topping stones flat, either deliberately for drainage or through incompetence.

 

[Nukeman948]

Yes you might find some good information or alternative ideas or pictures on other sites, but you must sort thru the noise to find a valid signal!
But problem is, a lot of the conclusions or ideas are provided based their cited, but not disclosed, calculations and assumptions. Point is there is a lot of difference of opinion out there...

Your screen name fits perfectly. It's All About Money.

Youtubers get paid by the number of viewers so when a guy shows up here promoting his own videos while also knocking videos from other youtubers, it kind of makes me suspicious of their motives. They talk in circles and never allow themselves to be pinned down with real numbers and calculations. Prove your assertions with facts and don't run off to your facebook page and try to get me banned there for calling you out here...to your face.

 

[StructuralMadness]

I think you are talking about me here. So first to clarify, I have been making hard core engineering videos on and off for 2 years now. I have a blog for about 8 years, written 600 answers on structural engineering with calculations in a lot of cases. For “ZERO” money. My YouTube channel isn’t monetized yet. It takes a lot of effort to get it monetized and you have to post videos regularly. Again I can’t do that because of lack of time.

Now stealing about content, I think you should notice that I made the entire video 45 minutes long. Talked about calculations in there, with a structural model of pool deck slab which showed failures, also discussed how the pool deck stayed up so far and brought in a research paper by “Hawkins and Ospina” for punching shear failure that was published in 2017. I did not bring in any technicalities because I wanted it easier to understand for the general population. Again it is not about exceeding the code specified capacity but it is about reliability analysis of materials and their actual capacity vs the code calculated capacity. I also brought in the concept of flexural induced punching failure and how crack propagation in flexure can compromise punching shear capacity as it loses aggregate interlock.

It was 2 weeks after the video I posted, BI released their video on the engineering failures on design side. I haven’t said that he stole my content because any good structural engineer can easily connect the dots and see things clearly. I am only questioning 3 points which doesn’t make sense from structural behavior/ member capacity standpoint.

Now, if I wanted to earn a lot of money, then Could have created 10 different videos with 100 different speculations, but I just finished everything in one, with all the dots connecting together. Because again monetization is not my goal here and it has never been. I earn enough for my family that I don’t have to put extra efforts to earn money, in fact I donate money annually and pay for under privileged child education in developing countries. So don’t start bashing someone without any reason.

Now I have no use of you and your comments anymore. Peace

 

[SFCharlie]

I don't know what if anything can be gleaned from this...
Champlain Tower Cars.. Must watch
but we might be able to get back on topic...

SF Charlie
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[Optical98]

SF Charlie,

Do you think the "#31...#53" etc, are the parking spaces?

 

[StructuralMadness]

I would second there. I do understand he finds a lot of information, but from engineering standpoint he hasn't made a lot of sense personally speaking. I watched one of his video where he said "I don't know what these guys on YouTube calls Puking shear or something." And that's when I stopped watching his videos.

Now going back to "Sounds"

I like your idea of Vierendeel truss action, but when we hear Nir's interview, he mentions that as soon as his mom went out to complain about noises, that's when they heard a loud boom and the cars caved in. Here is the link to his video. So, if the noises were coming from above, prior to complaints, then does it mean something failed prior to deck collapse? It is the timeline and witness's documentation about hearing noises vs the deck collapse that doesn't make sense. Everyone knows that deck collapse prior to the building, and the creaking noises and CMU wall cracks could have occurred only when the building was trying to support the buckled / failed column. Then how does the noises coming prior to the deck collapse make sense?

Edited to paste the link of the interview:

https://www.cbsnews.com/video/son-s...xZat_yyolak0F_z3OF06FAP8m7Hn5mEpHVp6m06BV28#x

 

[Nukeman948]

don’t start bashing someone without any reason.

My reason was clear in my first post to you.
You failed to address the sleazy move of destroying my reputation on facebook.

Yeah, we're done.
Bless your heart.

 

[SFCharlie]

Do you think the "#31...#53" etc, are the parking spaces?

I don't know anything you don't, but seems like an obvious guess



SF Charlie
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[gonefishing2]

I also brought in the concept of flexural induced punching failure and how crack propagation in flexure can compromise punching shear capacity as it loses aggregate interlock.

StructuralMadness,

If you go back to when the Association was complaining that 87 Park Construction vibrations were shaking CTS, you have to wonder if they are saying the structure is swaying? What effect was this having on the slab to column connections/joints throughout the building?

You also have to wonder why some folks had to float a very thick layer of thickset mortar to level their condo floors before installing hard tile floors?

So, I think your flexural induced punching failure is definitely an interesting possibility and seems it would explain the swaying from construction next door and basically lead to the building movements were basically tearing the joints/connections apart over time a little by little?

Was the swaying induced by skinny columns and the poor punch shear reinforcement just made the joints/connections more vulnerable?

It is not clear to me that the building was not having problems before the patio deck, but their marriage with the common beams at drop slab area led to all movements affecting both the patio deck and the building.

 

[SFCharlie]

Then how does the noises coming prior to the deck collapse make sense?

1. I don't know...

2. 1st punchthrough "catenary action" 2nd punchthrough "catenary action" 3rd punchthrough "catenary action" 4th punchthrough ???

I never heard of "catenary action" before, catenary is the name of a curve in my world???

Catenary action is a load mechanism that is developed to resist the additional loads as a result of sudden column loss and prevent disproportionate collapse. Buckling restrained braces (BRBs) have been widely adopted as a dependable lateral load mechanism since the early 1990s.

Catenary action in steel framed buildings with buckling restrained braces


SF Charlie
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[gonefishing2]

I don't know what if anything can be gleaned from this...
Champlain Tower Cars.. Must watch

About 30 seconds in, the red car in your video reminds me of the first muscle car era. For Example, I offer this image

More Info: It is actually a Train Blower and he blew head gaskets just blipping the throttle. Not an Engineer Designed Bolt-On! Just a junk yard find, that they decided to bolt on..... Or as they used to say, this was NOT a 'Blue-Printed' System Upgrade for this Engine!

https://www.musclecarszone.com/supercharged-chevy-camaro-blower/

 

[SFCharlie]

Swaying and lack of sheer walls seem connected to me?

SF Charlie
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[SFCharlie]

the first muscle car era

Is that a compressor between the carbs and the engine compartment??? Looks more like todays electric motors only much larger?


SF Charlie
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[gonefishing2]

SFCharlie, Yes the HVAC technicians use the compressor on top of the motor to run air tools while on the job! That way they can write off their auto investment!

 

[gonefishing2]

Agree, but without sheer walls, it is left to columns/slabs to provide lateral support is my understanding.

 

[MaudSTL]

I like your idea of Vierendeel truss action, but when we hear Nir's interview…

This is Thread #11 and you’re late to the party. So, to help keep us from going down a rabbit hole we’ve already visited, here are the key events that surviving witnesses reported in many corroborative sources which are cited in the second tab of the timeline spreadsheet.

All of these events have multiple witnesses and credible time stamps or ranges. That is why some engineers are considering structural failure scenarios that are compatible with this sequence of events.

[ol 1]
[li]11 PM to 1:10 AM, knocking sounds like hanging pictures or construction (111,) increasing in intensity over time.[/li]
[li]1:10 AM, a collapse like a collapsed wall (111) or something with the elevator (lobby.)[/li]
[li]1:15 AM, deck collapse viewed as a garage collapse (seen from the lobby, and heard from 111 and the elevator.)[/li]
[li]1:22 AM, building collapse.[/li]
[/ol]

We have already discussed that the perceived direction (from above) of the first two events is not necessarily meaningful.

 

[SFCharlie]

it is left to columns/slabs to provide lateral support is my understanding.

SF Charlie
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[Reverse_Bias]

Literally every 'chunk' in the "Slide 10" photo is just smashed up concrete.

That area near the garage ramp really got crushed badly. The east side of the building pancaked right on top of it. It's not going to be easy figuring out what happened to the objects in the tiktok video.