Miami Beach, Champlain Towers South apartment building collapse, Part 15 32

[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
Miami Beach, Champlain Towers South apartment building collapse, Part 12
Miami Beach, Champlain Towers South apartment building collapse, Part 13
Miami Beach, Champlain Towers South apartment building collapse, Part 14

SF Charlie
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[Optical98]

Demented

Their model "Slab self-weight of 150 pounds per cubic foot (pcf). (Assumes 9.5” slab everywhere, as detailed in 1980 structural drawings.)"

Wasn't it determined that was only up to the 8th floor, the slab thickness?

 

[Demented]

Does their model even go that high? I didn't get the best of read on it, but to me it read as though they've only modeled specific locations to run simulations on, or only up to the lobby level. Seems to me they've gotten impatient and just decided to go with one set of drawings and ignore as builts. I don't know, doing knowingly wrong simulations doesn't sit right with me.
Per 1980 plans, Basement is 9", Lobby is 9.5", 2nd to roof 8".

Edit:

2nd not boxed in red is taken from an adjacent page of the same 1980 revision plans.

Why they no read?

 

[MaudSTL]

Looks like the Miami Herald’s story

The Herald built a computer model to explore how Surfside tower fell. Here’s what it showed
is no longer behind the paywall.

Is a Pulitzer Prize in their future? Or will the NYT fight back? Stay tuned…

 

[fel3]

"The Herald built a computer model..." Because THIS is what reporters are good at and should be doing.

There were lots of ways to write an accurate headline here and The Herald wrote the worst one. Why not "The Herald commissioned a computer model..."???

============
"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill

 

[Reverse_Bias]

I think the Herald article rejects it's own computer model in the first few paragraphs
The witnesses described the collapse sequence as a three-part failure, each with distinct sounds
Then from the model they conclude after the two pool deck collapses, the first floor of the building caved in just before the building fell. That would be 4 collapses, unless the building fell instantly after the first floor caved so witnesses never heard a gap. Another thing that makes the first floor cave in theory not that appealing is that the 711 ringcam showed a warping wall prior to the collapse and 611 reported a crack opening up. This indicates something was wrong with the entire X11 stack, not just the first floor.


Speaking of the X11 stack here's another reason to doubt the model.
Finally it shows it is unlikely that the collapse of the building initiated under Unit 111, as has been suggested, since the additional structure there protected that area of the slab; it is more likely that the damage to the level-one slab within the tower propagated north and east from the gym and the slab-to-core wall connection.
That "additional structure" was laying on the ground in the TicTok video if that's what they're talking about.

They admit it's a very incomplete simulation, so I'm taking it with a grain of salt.

 

[AusG]

Everyone loves a model and maybe this is a half-step forward IDK, but what would be a real step forward is more interviews to fill in gaps where possible, and more heat on officials to release basic data. Both of these things are more in a newspaper's wheelhouse than detailed engineering from sparse info. I suppose publishing this might possibly chisel loose something new, we'll see.

 

[MaudSTL]

… the two pool deck collapses,

I don’t see the Herald claiming there were two deck collapses. Instead, they state,

“At 1:15 a.m. the western half of the pool deck and part of the valet parking area collapsed in one loud cascade of concrete.”

 

[Reverse_Bias]

I don’t see the Herald claiming there were two deck collapses. Instead, they state,

“At 1:15 a.m. the western half of the pool deck and part of the valet parking area collapsed in one loud cascade of concrete.”

Yeah that was poor wording on my part. Nobody knows what the first "wall collapsing" noise was.

 

[Jeff Ostroff]

If anyone owned a Tesla where would they charge it in that parking garage?

 

[Demented]

One of the many EV rapid charging stations located up and down Collins would be my guess.

Precision guess work based on information provided by those of questionable knowledge

 

[AutisticBez]

Can't wait for the CTS Lego set. We can test out all the various theories, replace some of the pieces at key areas with cheap Lego knock off brands from China. Should be an accurate simulation.

If you ask me, I think a combination of failures caused this.

First, the pool deck disconnected with the south wall because old damaged rebar from decades of condo board not maintaining it. Maybe a forklift drove on it, unconfirmed. Maybe 87 did it.

Then the unsupported planters near valet went due to someone forgetting to put a beam under them when converting to new design. Then tarpaper fell from the roof falling through a crack in the pool deck dropping next to a car causing it to swerve and hit the missing column.

X11 felt sorry for the column and fell on the car for revenge. End of story. Did I miss anything?

 

[Demented]

Screw LEGOs, we need K'Nex sets.

Foundational issues. I really think there's issues with the piles, especially the tension piles.

 

[Red Corona]

> The Disappearance of 87th Terrace and How it Relates to Surfside Collapse - Lawsuit Analysis Part 2

Interesting stuff. Thanks for posting the link to the next video.

​

It's pretty clear that the construction of 87 Park is extremely dodgy, and probably illegal in the way they acquired the street land. Certainly at least deeply unethical, since they got all the relaxations in the rules on the basis that they were going to keep the existing hotel and then they turned around and changed everything.

It's much more difficult to prove that their construction caused CTS to fall down though.

 

[MaudSTL]

The Miami Herald is going after the project next door. ‘The city will help us.’ Miami Beach took cash, fast-tracked tower on Champlain’s edge

>>>>>Edit: Looks like it’s behind the paywall after all. Here’s a link to the archived version.

 

[AusG]

So...have I got this right?...Surfside's quick ask-no-questions post-facto-approved questionable building was possibly compromised by Miami Beach's quick ask-no-questions post-facto-approved questionable construction and all that will be left to consider, after the lawyers have all finished, is how to split the remaining 38c among the surviving families?

The County's crime-scene tape is making more sense now.

 

[Demented]

I need to get something straight too.
Is this pile driving damage causing vibrations all hinging sheet pile driving, and only sheet pile driving? I think I've been wrongly assuming they've also been talking about regular ol' impact hammering of piles, not just the gentle foot massaging vibration driving.

Precision guess work based on information provided by those of questionable knowledge

 

[AusG]

From the Building Integrity video I got the impression it was all vibration of sheet piles they were upset about, but the details will be in the text of the plaintiff's court submission, if you want to plough through it.

 

[Demented]

I made it about 3/4 of the way through, there's a lot of BS to sift through, but seems the main complaints do ONLY revolve around brief vibratory sheet pile driving and the use of a tractor crane (Assuming they meant crawler crane but have no idea as to anything they're arguing). Complaints over continued construction noise between 8AM and 5PM, Sunday-Saturday also being their main bit of evidence as to those involved in the construction of 87 Park ignoring warnings that will damage CTS.

The suit clearly states NV5 inspected CTS in 2016 and documented ALL existing damage to the CTS structure. However, the suit fails to show any of this evidence and only shows Morabito photos from 2-3 years past showing the damage we've all seen already. Those NV5 photos sure would be nice to see, as according to the suit, they did contain photos of existing cracks in drywall of interior units and existing stucco damage.

I thought there was more to it, but nope, nothing. This suit will either be dropped, or defeated easily. The complaint seems to focus around certain verbiage as evidence of this being damaging work, not actual proof damage was done.

Precision guess work based on information provided by those of questionable knowledge

 

[MaudSTL]

Part 3 of Building Integrity’s Josh Porter’s analysis of the lawsuit against the sheet pile driving neighbor.

https://youtu.be/sqvqY4H_2hI

 

[spsalso]

After viewing Episode 3:

Mr. Porter says, in regard to a photo of the CTS wall, that "...you're missing sections of block..." On examining the photo, the above-grade wall does seem to be resting on concrete block. Is this below-grade concrete block also supposed to be holding up the now-fallen pool deck? If it is not, why would it's condition matter? Actually, it appears that the concrete blocks did a pretty good job, as the above-grade wall is still standing. Even with those missing blocks.

There is a comment that the walkway was "pitched", and that view was supported by the fact that the gravel was below the level of the walkway surface. Is the walkway itself "pitched"? If it is, why is not the slope of that pitch mentioned somewhere? If someone had put another couple of inches of gravel there, apparently the area would NOT have been pitched. At least, following the logic I heard. Is that missing two inches of gravel the reason CTS fell down?

This area, being outdoors, will be naturally wet during inclement weather. There appears to be an assertion that the CTS wall was made "extra" wet by the construction of this path. I would like to hear that concept developed by the CTS people.

I am curious at the level of water intrusion (in this outdoor place) over the last 40 years. Was that area of the wall bone-dry until construction next door? Was it wet? How wet?

The lawsuit apparent asserts that the pool deck became detached from its supporting wall (caused by the poor construction practices nextdoor). I note that there were no photos or description of the failed connection. What was supposed to keep the pool deck attached to the top of its supporting wall? What did it look like after the fail?


spsalso