Miami Beach, Champlain Towers South apartment building collapse, Part 09 139

[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

SF Charlie
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[davidbeach]

How about we bifurcate this? Part A can be facts as they become available, maybe a handful of posts a week for months to come. All the noise in Part B can then be ignored by 98.75% of us.

I’ll see your silver lining and raise you two black clouds. - Protection Operations

 

[SFCharlie]

“One of the conditions we have to consider before launching [a technical] investigation is if funds are available,” says Jennifer L. Huergo, a NIST spokesperson.

Miami-Dade Building Officials Suspect Poor Maintenance In Surfside Collapse (ENR)


SF Charlie
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[SFCharlie]

DISASTER & FAILURE STUDIES
Has links to stories like...
Update on NIST’s Investigation of the Champlain Towers South Collapse

Cameras and lidar used by NIST and its partners scan and record the site of the Champlain Towers South condominium.
Drones carrying cameras are being flown over the site to help with the geotagging of evidence and to capture changes at the site.

NIST will be deploying an electronic evidence tagging system that uses RFID chips so that electronic records are associated with every piece of evidence collected.

NIST has installed accelerometers to measure building vibrations and a seismometer to measure ground vibrations at the Champlain Towers North condominium

NIST is in the process of putting together the National Construction Safety Team that will lead the technical investigation.

SF Charlie
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[spsalso]

"Building officials of Miami-Dade County suspect deferred maintenance rather than weak building codes or an inadequate 40-year recertification process..."

So those are the three choices.

Apparently those building officials never thought of:

incompetent design

incompetent execution

incompetent inspection

corruption

sleaziness


A person could wonder why.


spsalso

 

[SFCharlie]

incompetent design, incompetent execution, incompetent inspection, corruption, sleaziness, extreme weather? Nope, none of that here!

--- oh, and I forgot, seawater flooding in the streets

 

[spsalso]

It has been claimed that like NTSB, NIST will take a year or two for the full report, but also like NTSB, they will release a preliminary report in less that a couple of months, that will only contain matters of fact, but no analysis. (They claim)

Unlike NTSB, they have not had news conferences several times in the immediate aftermath. These usually feature the lead investigator making a presentation and answering reporters' questions.


spsalso

 

[spinspecdrt]

 

[SFCharlie]

These usually feature the lead investigator making a presentation and answering reporters' questions.

or the chairman of the board propounding on his stature and impotence I mean importance.


SF Charlie
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[Brian Malone]

"Wow. Sounds a bit supercilious to disqualify any comment by any person not listed as a structural engineer."
I don't interpret the criticisms being put forth against some of the posts as saying only structural engineers should be able to comment. I am not a structural engineer but I am disappointed by many of the multiple posts by some who have taken photos from multilisting RE sites and pointed to 'deformations' and 'misalignments' and said look at the evidence of pending structural failure. RE multilisting photos are taken with wide-angle optics and digitally warped/stitched to look nice. One post asked about the ovoid witnesses on the concrete surface of a concrete sample and posited this looks like some type of boring and post-op concrete patching. Until called out this comment as intimating shoddy work and nefarious activities were afoot. Trying to use the grainy low-res security camera video as conclusive evidence to say 'look, the penthouse caused this' seems uninformed and at worst bordering on conspiracy mongering. I have checked out enough of this listing to see I have seen enough until NIST comes out with an official report. Everyone have fun and thanks!

 

[SFCharlie]

Grassy Knoll

did that just teleport in from Texas?

SF Charlie
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[Debirlfan]

Something just occurred to me. The only people who escaped were in 111 and 611, directly above. They escaped because they ran (respectively) to the lobby and the stairs by the elevator.

I had always assumed that perhaps other people had attempted to escape, but had tried to use the other staircase, and been killed when it collapsed. However, the articles quoting the Israeli team state that virtually everyone was found where they were expected to be, which suggests they didn't attempt to flee.

So, were the residents of the -11 units the only ones who received any warning?

 

[waross]

One post asked about the ovoid witnesses on the concrete surface of a concrete sample and posited this looks like some type of boring and post-op concrete patching.

I got a kick out of that one. My thought was that anyone who had not seen enough plywood to know what a standard patch looks like when knots are cut out, and who has never seen a pattern left on fresh concrete by wooden forms does not have enough real world exposure and has no business even guessing about structural matters.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[spsalso]

A modest proposal:

For all these buildings being (re)-inspected, allow only people from out-of-state, with NO business ties to Florida, to do the inspections.

Everyone in Florida should recuse themselves in this matter. We just don't want even the appearance of self-interest here. Right?

And I'm sure the building officials of Miami-Dade county would agree.

Locally, I think we could spare a couple of people for awhile, for the common good.


spsalso

 

[SFCharlie]

Trying to use the grainy low-res security camera video as conclusive evidence to say

I never intended the grainy low-res security camera video as conclusive evidence of anything. When I looked at it frame by frame, it was more worthless than I had imagined... Sorry!

SF Charlie
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[dik]

the issue might be somehow related to structural issues...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[MaudSTL]

So, were the residents of the -11 units the only ones who received any warning?

Check the timeline I posted above on this page.

I have been unable to find any indication that the surviving witnesses heard a warning on the side that collapsed. The Nirs (111) got lucky…they had activities that kept them up later than usual that night, and their apartment was right above the epicenter of the collapse. So they were able to hear and feel the building’s attempts to redistribute its load and get out of the building in time. Ileana Monteagudo (611j was awakened by the deck collapse, which she calls a “supernatural force.” When she saw symptoms of impending collapse and ran to the staircase, luck played an important part for her too: she chose the staircase that survived, instead of the closer staircase that didn’t.

After the building collapse, several people who were in the part of the building that remained standing said they heard the alarm after the building had collapsed.

 

[nessman]

Miami-Dade Building Officials Suspect Poor Maintenance In Surfside Collapse

Not surprising. If the building had major structural issues it would have failed a long time ago. People gotta remember - something like this isn't caused by a single event but a series of events in the days/hours/minutes leading up to the collapse, caused by prolonged deferred / neglected / poorly executed maintenance over a period of many years since the building was first constructed.

The building survived the initiating event (likely the pool deck collapse outside of unit 111) and remained standing for 7 to 15 minutes. That was plenty of time for evacuation which never happened (lack of emergency planning). The weakened concrete/rebar could only hold redistributed load for so long. If the same initiating event happened 40 years ago when the building was finished it would have likely survived.

Gotta ask why.

Why did the building collapse? Because the pool deck failed. Why did the pool deck fail? Because of water infiltration into the structure. Why did water get in the structure? Because of failed waterproofing. Why did the waterproofing fail? Because it hadn't been maintained over the years. Why wasn't it maintained? Because the condo association likely didn't have the wherewithal to have the deck waterproofing inspected / replaced at regular intervals. Why did that happen? Because the condo association aren't subject matter experts in building maintenance and/or didn't feel the expenditure was necessary. Etc... etc...

 

[Optical98]

MaudSTL and Debirlfan

Unit 904, Mother and daughter of Gonzalez family. They heard something and ran out their front door into the hall, took 5 steps and 9th flr fell to 8th..
It's a tough article to read, they're both still in the hospital I believe.

I can link the article if you need.

https://www.nbcnews.com/news/us-new...ld-not-be-alive-after-condo-collapse-n1273597

 

[Debirlfan]

Unit 904, Mother and daughter of Gonzalez family. They heard something and ran out their front door into the hall, took 5 steps and 9th flr fell to 8th..
It's a tough article to read, they're both still in the hospital I believe.

Ah, that's my point. 111 heard noises over a period, and had time to go back and forth to the lobby. As I recall, 611 had time to throw on clothes, gather a few items, and make it to the far stairs. Whereas 904 apparently only had seconds, and other tenants either heard nothing, or didn't have time to respond. To me, that suggests there was initial movement/sounds which were mostly contained to that column and not felt/heard in the rest of the building. Whether from above or below, it seems there must have been a gradual failure centered within the -11 column.

 

[waross]

Was this mostly a retirement condo?
Noise doesn't always wake older people when the hearing aids are in the charger or on the end table.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!