Miami condo collapse

[dad911]

Video from a camera inside one of the units:

https://twitter.com/_rosiesantana/status/1407970894924992512?ref_src=twsrc%5Etfw%7Ctwcamp%5 Etweetembed%7Ctwterm%5E1407970894924992512%7Ctwgr% 5E%7Ctwcon%5Es1_&ref_url=https%3A%2F%2Fd-13831536054085327483.ampproject.net%2F210612010700 0%2Fframe.html

[sugarwood]

Originally Posted by jyl

Reviewed all the minutes and notes from the condo association meetings, read all the engineering reports and bids, read the emails between board members, interviewed the condo association board president and others.

I told him he was crazy..

Well, at least that last part is right.
I agree, he's totally crazy.

[sugarwood]

These are the 2 most important posts in this thread.
It was a sinkhole effect where the ground collapsed.
You can see the platform around the pool is caved in, yet the umbrellas are intact.
We can end the speculation now.

This may have implications beyond the 2 Champlain Towers

Originally Posted by Racerbvd

https://www.newsbreakapp.com/n/0afIH9Pt?&share_destination_id=NTA4ODk2MDgtMTYyNDcyNDQzNTQ3O Q==&s=a7&pd=03RWi8Gl&hl=en_US&lp=v3

Originally Posted by David

https://www.insider.com/woman-was-on-phone-to-husband-as-miami-block-collapsed-2021-6


A woman stood on the balcony of her fourth-floor apartment as the Florida condominium collapsed told her husband on the phone that she could see the pool "caving in" seconds before the line went dead, Sky News reported.

Cassie Straton was speaking to her husband, Michael, from their balcony on the south side of the Champlain Towers when she noticed the building started shaking in the early hours of Thursday, her older sister Ashely Dean said.

"Suddenly she says, 'honey, the pool is caving in. The pool is sinking to the ground,'" Dean said, according to Sky News.

"He said, 'what are you talking about?' And she says, 'the ground is shaking, everything's shaking' and then she screamed a blood-curdling scream and the line went dead," Dean added.

[The Synergizer]

Faces of the "missing."
https://www.dailymail.co.uk/news/article-9729475/Faces-missing-Officials-searching-156-people-three-days-Miami-condo-collapse.html

These were not old geriatrics, but also real young vibrant people.

[dad911]

Originally Posted by sugarwood

These are the 2 most important posts in this thread.
It was a sinkhole effect where the ground collapsed.
You can see the platform around the pool is caved in, yet the umbrellas are intact.
We can end the speculation now.

This may have implications beyond the 2 Champlain Towers

The following from the engineer's report led me to believe at least part of the area under the pool deck was open and/or underground parking:

[Bill Douglas]

I'm not saying this was the case in the condo collapse. But some dodgy construction companies put less cement into the concrete mix to cheapen it. They also build the next floor (putting the lower floor under stress) before the previous floor has properly cured, to speed up the building progress.

[Crowbob]

The infiltration of water (seawater) into the concrete resulting in the corrosion of the rebar in addition to sketchy concrete recipes is what caused this.

Proper caulking of the balconies and other joints was (and is) absolutely crucial to maintaining the integrity of the structure.

My guess is, during construction, whomever did the caulking was completely unaware of the importance of what they were being paid the minimum to do.

[thor66]

Originally Posted by Bill Douglas

The lawyers will be delighted.

They'll be sitting around in a bar saying "OK, which side do you want to be on? You say this, then I'll say that, so we can drag it out for years while being on full pay."

now we know how to update Bleak House for TV

[Coverman]

We have had our own high rise scandal here. Fire spreading upwards via external decorative cladding acting I think as a conduit. The cladding,sold for use this use, turns out to be highly inflammables. 70 odd people died in one building , but now hundreds of others with this cladding have been declared unsafe. The poor individual owners are having to pay huge sums, which most cannot afford, to have the buildings made safe. In the meantime, unsurprisingly, their properties are unsaleable. This aluminium cladding is supplied by a French company, although I think the ultimate owners are either from the US or Canada. I cannot understand why our Government isn't making this company pay for everything.

[URY914]

Originally Posted by Coverman

We have had our own high rise scandal here. Fire spreading upwards via external decorative cladding acting I think as a conduit. The cladding,sold for use this use, turns out to be highly inflammables. 70 odd people died in one building , but now hundreds of others with this cladding have been declared unsafe. The poor individual owners are having to pay huge sums, which most cannot afford, to have the buildings made safe. In the meantime, unsurprisingly, their properties are unsaleable. This aluminium cladding is supplied by a French company, although I think the ultimate owners are either from the US or Canada. I cannot understand why our Government isn't making this company pay for everything.

The lack proper building codes was the problem with that building.

[URY914]

Originally Posted by Bill Douglas

I'm not saying this was the case in the condo collapse. But some dodgy construction companies put less cement into the concrete mix to cheapen it.

This type of comment has no basis in fact.

Construction companies don't mix their concrete. They order it from a ready-mx company. The mix design is spec'd by the structural engineer. A testing company tests it on site and in the lab. All four of them are independent of each other.

[TimT]

This type of comment has no basis in fact.

Quite a bit of that going on in this thread...

From the incorrect statements about rebar...waterproofing, etc.

Usually the only variable to concrete delivered to a job site is the amount of water in the mix. Typically central mix concrete is batched with 90% water added at the plant.. A 10% window is allowed for adjustment at the site for workability, etc..

Of course sometimes a contactor will add water such that the mix now has 125% design water in it.. so the laborers and finishers don't have to bust ass so much.. even with extra added water , the concrete cylinder breaks exceed the design strength!

Now batching is quite accurate.. sand, stone, cement, admixtures are scaled and added automatically...in the 80's it may have been a guy watching from a dirty window, looking at scales.. and a guy climbing on a truck dumping some air entrainment or retarder in the drum..

Transit and truck mix concrete are rarities in the NYC area..

This failure will probably be blamed on lack of preventive maintenance... The building was probably shoddily built...but I bet little or no maintenance has ever been done..

[wilnj]

Originally Posted by Coverman

We have had our own high rise scandal here. Fire spreading upwards via external decorative cladding acting I think as a conduit. The cladding,sold for use this use, turns out to be highly inflammables. 70 odd people died in one building , but now hundreds of others with this cladding have been declared unsafe. The poor individual owners are having to pay huge sums, which most cannot afford, to have the buildings made safe. In the meantime, unsurprisingly, their properties are unsaleable. This aluminium cladding is supplied by a French company, although I think the ultimate owners are either from the US or Canada. I cannot understand why our Government isn't making this company pay for everything.

I believe you’re referring to Aluminum Composite Panels. Very common in rain-screen systems. I think what you’re referring to is an unanticipated consequence. Most codes don’t contemplate a fire on the outside of the building unless another is immediately adjacent.

Modern specs for ACM call for a fire rated core for this reason.


Sent from my iPhone using Tapatalk

[URY914]

These closeups show rebar but I don't see post tension cable hanging anywhere.

[TimT]

I don't see post tension cable hanging anywhere.

Nor do I, and actually what I see of the rebar, it doesn't appear to be in bad shape, a little corrosion where the balcony meets the interior..

[javadog]

Post tensioned cables weren’t in widespread use in buildings like this one when this one was built. In any event, they wouldn’t have been in the columns and those were what failed. It’s obvious that there was some rusting of the rebar in the balcony slabs and the report indicated the previous repairs were done improperly.

I don’t think any of that matters. What looks most likely to me is that the foundation failed catastrophically. If that description by the woman in the building to her husband is correct and the slab adjacent to the pool collapsed before the building fell, then I think it is most likely that the failure was begun in whatever this building was built on. I have no idea if there are piers extending into limestone, or what the foundation might be.

[p911dad]

Originally Posted by Crowbob

The infiltration of water (seawater) into the concrete resulting in the corrosion of the rebar in addition to sketchy concrete recipes is what caused this.

Proper caulking of the balconies and other joints was (and is) absolutely crucial to maintaining the integrity of the structure.

My guess is, during construction, whomever did the caulking was completely unaware of the importance of what they were being paid the minimum to do.

This. Back in the 1970's and 80's I was involved with a lot of highway construction, and we used a lot of Portland. As I recall, the rebar back in those days was mostly uncoated, raw steel. As time and salt on the highways wore on, many bridge decks failed (not catastrophically, basically the surfaces spalled badly because of rusted rebar. Later on, factory coated rebar appeared reducing the rust problem. If the condo building was build in 1980 with uncoated rebar (seems likely) in a high salt environment and no one keeping up with the waterproofing, then eventually the salt will get to the rebar and rust would be unchecked. Eventually the concrete is damaged. The rebar is vital to the integrity of the structure.

[pmax]

Originally Posted by dad911

Hundreds or thousands of gallons of gas from the lower level cars/parking.

Li batteries, damaged in all likelihood, and water are a bad combination.

[Bill Douglas]

Originally Posted by URY914

This type of comment has no basis in fact.
.

The comment is based on fact. This is the reason buildings fall down in Italy. You guys obviously have checks and balances - that's good. But the comment certainly was based on fact.

[Coverman]

The fire in the London tower block was started at a refrigerator inside the building. Somehow it spread to the outside,( maybe through an open window?) then rapidly spread upwards via the external panels.