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Miami Beach, Champlain Towers South apartment building collapse, Part 17 14

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@MaudSTL, thank you very much for clarifying, we are completely in agreement on this aspect now.
 
It may seem like a pedantic exercise to get the labels and time stamps proper, but it sure keeps things on track. Thanks Maud for your contributions.
 
MaudSTL said:
Sarah Nir and Gabe Nir did indeed park in Space 14 near the east stairwell when they arrived at around 12:30 AM. They have never stated explicitly that they used the staircase instead of the elevator to get to 111. But your theory does make sense.

Thanks MaudSTL for clarifying that.

Edit: Red Corona I agree with your post that 1:10am noise could have been as you cite, and yes I mixed up the two witness groups and events.

For those who can think outside of their own sandbox, it makes perfect sense, without 'stretching imagination', that 'perhaps' the first shedding of some concrete was related to first movements of slab as it sagged and retracted from South Wall. If I understood IanCA correctly and from looking at photos of South Privacy Wall, it appeared that Slab at wall extended 16" south from the inner edge of the northern side of the 8" concrete parking garage wall.

Perhaps there was a slight pause as slab retracted, and shed some layers of the lower concrete cover below rebar grid? This partisl shedding would seem logical, since the bottom edge of slab would be in tension in some places and in compression in others, due to the butterfly forming under parking deck near south wall.
 
@IanCA and @Sym P. le, You’re welcome.

It is unfortunate that the surviving witness statements do not contain directional clues that point to the location of the deck collapse trigger. The banging that went on for hours and the loud crash at 1:10 did not point to the deck for any of them. In 111 the bangs and loud crash seemed like they came from above. In the lobby the loud crash seemed like it came from the elevator (and no one has asked Shamoka Furman if she also heard the bangs that they were hearing in 111.) No one has ever asked Eric and Tamar Zion what they heard and saw when they used the garage earlier in the evening.

As for the deck collapse itself at about 1:15, it was apparently so fast, without any perceptible pauses, that the people on the first floor and across the street all perceived it as one single crash. Yet the loud sound of this crash is not what woke up Ileana Monteagudo in 611 (who said she was awakened by a “supernatural force”) or the late Cassie Stratton in 410 (who told her husband she woke up because the building was shaking.)

So the witness statements give us a timeline of major events and some general clues about what could possibly have been going on, but all the possible collapse triggers will have to be identified and ranked forensically. And this forum only has access publicly available information like photographs, so it’s frustratingly similar to reading tea leaves.
 

I agree with reading the tea leafs, and I do think that skill is a speciality gained long after the college basic broad ‘cook book’ foundation is poured.

Where I live, there is frequent DoD missile testing and explosions, perhaps 15 to 20 miles from my house, which is on slope of limestone mountain. The effects shake the ground and my house.

I know the direction the testing is coning from my house, yet I have a hard time pinpointing the direction of the incident sounds from the reflected sound waves At times, I would say it came from the mountain which is the opposite direction of the incident sound.

I am a OLD technical person, whereas the eyewitnesses most likely have never been exposed to this intensity of heavily reflected sounds in a concrete structure. Yes it was one event, but I see at least 4 distinct steps. Initial loss of concrete somewhere (likely parking deck slab), parking deck/patio deck collapse, middle building collapse, and East side collapse. The limited ‘witness’ information in public domain is not something that is freely released, especially after everybody lawyered up. In fact, once you lawyer up, ain’t nothing released without a specific agenda for that release.

The collapse was not a single event. It was a time phased event, and it happened very quickly from initial collapse sound. Popping, booms, creaks went on longer as parts of slab/columns progressively failed and transferred loads internally.

Time phased means variations in frequencies and intensities of incident and reflected sounds. So one event is not just one ‘boom’ that is quickly attenuated.

So for the layman witness to say the sound came from a certain direction is not necessarily the direction of the incident sound source. There will be lots of reflected sounds associated with original source and that will smear the perception.

 
> @FJB However, if their parking spot was say in North East Corner near the East Stair Tower and I lived on first floor, I for one would take the stairs as the shortest direct path to my apartment/condo

I think this was answered already, but I was talking about the Vazquezes (apologies if that wasn't clear) and we know they used the lift from their statements. So I don't think there's any reasonable way the garage could have been visibly seriously damaged and them not noticed.

Ed: And yes, big thanks to Maud for keeping us all on the straight and narrow wrt witness statements and the timeline!

Ed2: Regarding the "energy" for those 7 minutes, I think this is a mistaken concept. The energy of the building is in gravitational potential energy, mostly, and not really relevant until the collapse. What was happening for those 7 minutes is that stresses were being applied which were very slowly bending or crushing important things (K and L 9 columns) and redistributing stress as those columns lost their strength. It seems like they failed pretty much simultaneously.
 
Red Corona said:
What was happening for those 7 minutes is that stresses were being applied which were very slowly bending or crushing important things (K and L 9 columns) and redistributing stress as those columns lost their strength. It seems like they failed pretty much simultaneously.

Thanks, Red Corona. What you stated is compatible with witness statements.

Gabe Nir in 111 said he felt rumbling beneath his feet after the 1:10 crash and also after the deck collapsed at about 1:15. In a later interview, he also said that he felt the building sway after the deck collapsed. He didn’t say either of these things mention the swaying in any of his contemporaneous interviews, but rather months later, in the Miami Herald “House of Cards” feature. So I have always wondered whether he was asked leading questions looking for support of their collapse theory. But what he said is certainly compatible with the description of how the structure redistributed its load in the last seven minutes.

Up in 611, Ileana Monteagudo woke up after the deck collapsed at about 1:15 and found her sliding balcony door so out of square that it wouldn’t slide. Then she saw a crack form in one of her living room walls. We have never had confirmation of which wall cracked, but my theory, based on how the furniture was arranged in a real estate listing, is that it was the west wall. But that is just a theory. At any rate, within minutes of the deck collapse the redistribution of stresses had already changed the geometry of her unit. A few minutes later, the Ring camera video that triggered at 1:22 also showed a geometric change in progress.

Remember too that the late Cassie Stratton (410) told her husband the building was shaking and it woke her up. Since she called him at 1:20 from the balcony, the shaking must have woken her up sometime between 1:15 and 1:19. Just before the building collapsed at 1:22, she told him the building was shaking again. So the load transfers may have briefly paused before the columns finally buckled.

>>>>>Edit: See correction above. I conflated statements about rumbling and swaying, and have corrected my comments.
 
I believe the Ring cam triggered twice. We have an initial nine static frames immediately followed by a second fluid scene followed by a few dark frames. (At least in my copy)

Are two time steps available?
 
Red Corona (Computer) said:
I think this was answered already, but I was talking about the Vazquezes (apologies if that wasn't clear) and we know they used the lift from their statements. So I don't think there's any reasonable way the garage could have been visibly seriously damaged and them not noticed.

Actually, it was late, they may have been tired or distracted - if their parking spot was near the elevator, it's unlikely that they were looking around much beyond right where they were driving. Plus, there's no reason for them to be looking up - so if the deck had started punching thru, they might not have noticed. How brightly lit was the garage (the cell phone shot down the ramp makes it look rather dim) and could initial damage to the deck have taken out any lights/wiring, making it even less likely they would have seen any damage? (Given the 'maintenance' or lack there of, a light or two being out probably wouldn't have raised any alarm.)
 
My understanding (from the video walkthrough of the garage the year before, and various Youtubers who've visited CTN since the collapse) is that the garage was normally lit, and so the lights being out because of a deck collapse would be even more noticeable. The deck could have started punching through, yes (I suggest that in my previous post actually), but not to the extent of any visible ceiling collapse on the underside imo.
 
I reached out to Shamoka last week but she has not responded to me. I will be at the Remembrance 1 year memorial at the condo collapse site Friday. I hope to meet up with the sister of cassie, who had called her husband at about 1:20 AM to tell him the pool deck collapsed, went the building collapsed and she was killed.
 
Jeff, I know that Shamoka is really struggling with PTSD, as are the other survivors. There are many questions for Shamoka listed in the Detailed Data tab of the Timeline, but I am not sure that this anniversary is a good time to ask her anything, as it would cause her to have to relive a deeply traumatic event.
 
Surfside building collapse: Security company to pay most of $1B settlement, attorneys say This is the first time I’ve seen in writing the claim that Securitas failed to train Security Guard Shamoka Furman to press the all-unit voice alarm. This story doesn’t mention the supervisory state of the alarm system, the lobby alarm switch being pulled, or any other details mentioned in the article about the security system log we have previously looked at.
 
Researcher Warns About Sea Level Rise Impacting Buildings Like Surfside Condo

As NIST conducts invasive testing, FIU researcher Randall Parkinson has published a paper in which he states that the ground water rose above the CTS basement level an average of 244 times a year between 1994 and 2006, and an average of 636 times a year between 2007 and 2020.
 
The judge just approved the one billion dollar settlement this morning after a hmorning after hearing. Here is the link to the AP story on it so this happens 1 day before the 1 year anniversary which was his goal originally. I will be down there at the site tomorrow for the festivities covering it.

 
It’s certainly understandable that the survivors feel punished by the $1B wrongful death settlement.. The $96M settlement for loss of property won’t allow the survivors to buy a similar property. All the suffering is so sad. The recent photo of Ileana Monteagudo makes her look like a different person.
 
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