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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[Debirlfan]

This snuck under my radar:
Emergency Works Taking Place This Weekend At Champlain Towers South Site

I think that's on hold waiting for permits. The irony....

 

[Demented]

@Demented - I looked at the condo association's letter to the owners from April 9 of this year, their balance sheet had a special assessment from 2016 for unit doors in the amount of $252,000 - guessing that hadn't happened yet as the money still appeared to be in their reserves.

They also mention the association having as-builts on file, I wonder if there really was a set floating around out there like a mythical unicorn, or some sort of holy grail...more likely they cobbled together a set of plans over the years as they had repairs and upgrades done, then referred to those as such.

@AutisticBez - I believe Santos81 confirmed that investigators are in possession of better-quality (than what the public has seen) video from several angles, and I'm sure they have more than what he's mentioned. Anything with better resolution is going to show some pretty awful details, given that people were out on their balconies...understandable that they wouldn't release those to the general public. I don't know what the protocol is as far as this being a crime scene but I'm sure that factors in as well.

@AllAboutMoney - I think the location of the additional penthouse had almost nothing to do with the structure itself, far more to do with proximity to the ocean. Better views cost money, stands to reason they'd put the most expensive unit in the building in a spot that would justify charging even more for it.

As far as I am aware the work was not done. They couldn't get an 80% majority.

As builts on file did exist, along with photo documentation of as builts. Surfside and Miami don't have it, so it's either missing from the storage unit, in the hands or Morabito or now investigators, or was stored on site and became collapse rubble to be found. It's gunna take a while to sort through all those skip loads.
Edit: Digital copies thankfully do exist with past contractors.


@Debirlfan
Is it even irony at this point?

Move forward with a rushed demolition, but ah, geeze, need a permit to keep something from collapsing in on itself.

https://www.bostonglobe.com/2021/08...ng-six-weeks-after-collapse-champlain-towers/

Miami orders residents to evacuate 8-story condo building six weeks after collapse of Champlain Towers

Residents of an eight-story condo building in Miami were ordered to evacuate after the building was deemed “unsafe” by city officials.

On Monday night, some six weeks after 98 people died in the collapse of the Champlain Towers South in nearby Surfside, residents of the 138-unit building lugged belongings to their vehicles, news outlets reported. They were ordered to be out by Tuesday morning.

“My grandfather just comes in the house screaming that we have to leave immediately,” said a resident identified by WSVN as Mya Ncastanedo. “If this building is demolished, there goes our property ... and all our memories from growing up here.”

The building was put on notice July 7 for several violations, including failure to obtain its 40-year recertification as safe to occupy.

“We felt the building occupants were not safe,” Miami Building Director Asael “Ace” Marrero told the Miami Herald.

On July 26, city officials met with residents who were concerned about the condition of the building, the Herald reported.

City staff inspected the building the next day and determined that the detached elevated garage had to be closed because of structural concerns, according to the newspaper.

Officials also told the building's property manager that the damaged columns in the main building's first floor “required emergency shoring.”

The city ordered the building's officials to submit a plan to fix the issue immediately, but never received any plans, officials said. The building also did not apply for any permits to make repairs.

On Aug. 5, city officials received a letter from an engineer saying the “building was safe for current occupancy while the emergency repair work continued,” the Herald reported.

The next day, an inspector from Miami saw work being done without a permit, and a stop-work order was issued.

On Monday, officials from Miami’s building department met with the condo association and the engineer. They found the columns to be “structurally insufficient.”

That's when the evacuation order was issued.

City officials told the Herald they're working with residents to find temporary housing.

Since the Surfside collapse on June 24, residents from several South Florida buildings have been evacuated because of structural concerns.

It's a clown show down here.

 

[AutisticBez]

Surely selling the property shouldn't be an option given the legal battles being brought forth.

 

[Demented]

Stipulations will be in place regarding what can be done with the property and when.

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

 

[arbitraria]

They need to sell in order to compensate victims and families, insurance alone isn't going to pay out enough to cover the losses.

 

[Debirlfan]

Is it even irony at this point?

Move forward with a rushed demolition, but ah, geeze, need a permit to keep something from collapsing in on itself.

I was actually thinking of the original construction and previous work on the building, not the demolition.

 

[MaudSTL]

For your convenient reference, I've updated the Timeline with details from the bodycam videos, and made some corrections to the details about the five survivors who were extracted from the pile. The main value of the bodycam videos was confirmation of the three stages of collapse from the lobby instead of 111.

Key events:
11 PM or sooner: Knocking sounds (like hanging pictures on the wall)
1:10 AM: 1st collapse (like a wall collapsed or something happened with the elevator)
1:15 AM: 2nd collapse (deck collapse)
1:22 AM: 3rd collapse (building collapse)

https://docs.google.com/spreadsheets/d/1vzmMPe83QyvpRYtduCJLarmGed1QDwwQ6Q77O1VRsJE/edit?usp=sharing

==>Please let me know if you have any additions, corrections, etc.

Over time, I would imagine Surfside and Miami-Dade may engage in a war of info releases as needed to improve their positions, so I will continue to monitor and update. The link will remain the same.

 

[Reverse_Bias]

The article I posted blamed the thicker columns on the valet parking ... Link

This mentions beams not columns. I read somewhere that the columns west were larger for hurricane support. It doesn't make much sense so maybe it was just hearsay.

That makes too much sense. Any thought about prevailing offshore winds at landfall in this? Where would the shear accumulate?

Hurricane winds would be potentially strongest in the onshore direction. Wilma was able to produce 100mph gusts out of the west though. The island is a row of buildings, so they may shield winds N-S and S-N winds a little. However, the building is wider along the E-W axis which would create more N-S drag. Best to just design it for high winds out of all directions.

A direct hit form Irma 2017 or Dorian 2019 would almost surely have have caused just as bad or worse of a collapse. The western side could easily have fell too seeing as they were afraid Elsa would knock it down with 50mph winds.

 

[AutisticBez]

I thought the columns west were larger due to them being further apart from each other to give a larger open feel to the front entry area. In hindsight, perhaps the same should have occurred to the east? I mean, here is the thing, is there a problem with over engineering columns? Maybe you make them double thick or like those big round columns you see. Like, do you really only want to get 40 years out of a building like this? With the right care this building could have been still up.

I think it's like this, you buy an old car for $5000, and maybe someone in a parking lot dings it, scratches some of the paint. You start to care less about your car, maybe you don't try to do as much work on it? Maybe your thinking soon you'll get a new one. But, I guess when your building is having concrete problems, maybe you don't really care? Maybe you want to rent it out and then one day the building gets demo'ed and you get a brand new condo on it's place? You think this building was just suffering from this type of lack of care for it? I mean, they put effort into each condo, but they didn't really care much for the public areas except for the lobby, because if you want to sell condo's you need to make a good impression true?

 

[12345abc6ttyui67]

Like everything, there is always a cost (not necessarily monetary, e.g. loss of internal floor space) associated with over engineering anything. The strive is always to make it 'just good enough'. Anything else is wasteful.

 

[AutisticBez]

Yeah but the cost of concrete and rebar is hardly your biggest expense compared to the entire building process and employing people onsite. A few inches here and there won't break the bank. I mean, you are spraying concrete everywhere, its surely not going to take much extra time.

 

[Sym P. le]

Brainstorming - the structural mass of the thirteen story east wing starts to decompensate (banging noises etc.) (wind?) thus imparting a lateral load at the pool deck level (northward?) triggering the deck collapse and consequently resulting in the entire structural collapse.

 

[Umbricus Agathopus]

@AutisticBez - what you have to understand is that the cost of materials isn't really concerning anyone - the money behind these projects wants floor space to rent/sell in order to make the project maximally profitable. They can't rent floor space occupied by structure. The only people that hate columns more than Architects are Developers. To a lesser degree, structural depth in floor systems "works" the same way.

The bottom line is - money funds these projects and that money wants the maximum sellable/rentable space which implies minimum structural volume. From an engineering perspective, as RandomTaskk points out, anyone can design a structure that won't collapse under load - good structural engineers design the minimum (i.e. - usually the smallest or lightest) structure that does the job.

 

[SFCharlie]

@‘NEW’ SFCharlie,

I finally realized what you were asking about.
[highlight #FCE94F]NEW[/highlight] SFCharlie
is a [highlight #FCE94F]NEW[/highlight] post by old SFCharlie


SF Charlie
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[SFCharlie]

Aug. 11, 2021, Update on NIST’s Champlain Towers South Investigation
"and every Saturday evening, he reads the Sunday news"

SF Charlie
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[gonefishing2]

Nerd Humor is very hard to convey in text, emails and forums without a great picture or video. I definitely was Not an English Major!

I guess I was tripping over my do-dads?

 

[waross]

Thanks SFCharlie. A lot of us were puzzled by that.

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

 

[rodface]

Still curious as to when, or what it will take, for investigators to learn the truth about the nature of the underground concrete piles.

I am unfamiliar with the amount of demolition that is performed when a site like this is to be redeveloped. Would all piles be fully extracted and the soil filled? Would they be left in place, and piles for the new construction have to work around these existing ones? I can't imagine that they would be re-used for the new construction in any way, shape, or form.

 

[Optical98]

Stalking horse bidder emerges for Surfside condo site offering $110M

https://therealdeal.com/miami/2021/...merges-for-surfside-condo-site-offering-110m/

 

[Optical98]

https://www.newcivilengineer.com/la..._NCE_EDI_ALL_DAILY_100821&deliveryName=DM4039