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Miami Beach, Champlain Towers South apartment building collapse, Part 08 20

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Optical98 said:
Demented, that red beam is haunting, because we know once the east end of it lost it's footing, that huge unit took a long bite out of
the #4 units, pulling down everything in it's path.

I still think the HVAC & roof anchors caused this, why:

The roofing & roof anchors work had gotten to the area of the HVAC unit and the "bootleg" penthouse.

The roof anchors were being installed incorrectly (on 6" cantilever slabs where 8" was required on the remaining portion of building - who knows what they did when they got to the HVAC and Penthouse. I'm sure the roof anchor company and the inspector knows.

Morabito appears to have a relationship with the roof anchor company. Why would they install anchors prior to structurally stabilizing the building. Why did Morabito send that email to the city AFTER COLLAPSE. Roof anchors weren't even needed, you could repair with cherry pickers and scaffolding. They had a cherry picker to the roof after collapse.

The roof anchor testing note on the plane required 5,000 lbs (ultimate failure load) testing where typically 2,500 lbs (2x design load) is performed to minimize structural damage.

Roof anchor inspection (and most likely observation of testing) was less than 18 hours prior to collapse. I requested the inspectors notes from the inspection that day from the city but they replied saying they posted it - they hadn't.

Construction noises came from "above" first per 111. We know walls cracked from the ceiling downwards per 611.

The Penthouse & 12th-10th floors collapsed first and slowly floor by floor to floor 8 from 904 (this information is new and wasn't available when I originally posted my roof theory in part 1 of this forum.)

Portions of the roof, Penthouse, and 10th-12th floors falling onto the pool deck would have hit the backside of the damaged columns in the remaining building engineers on site after collapse suspected brought down the pool slab. It was damaged on the side opposite the lobby level parking across from x10 units and deformed horizontally.

Perhaps everyone is already aware of the roof anchors causing this and that is why the police have said that is a criminal investigation - they didn't have a roof anchor permit until less than 18 hours prior to collapse yet clearly had done a significant amount of work.

Standing buildings don't just fail, they almost always fail under unusual loading or during construction. The roof anchor work was the trigger.

Regarding water in the basement during recovery, water is going to get in when the pumps are turned off, there is no roof, and the perimeter walls are damaged.

-W
 
@Thermopile
Have you any idea where the callout for the concrete beam is? Best I can gather is it's a BM1, BM34, BM36, or BM38.

Precision guess work based on information provided by those of questionable knowledge
 
What I am finding is a Carrier APD080 which is replacement model number on permit doc's, weights 2610 lbs. Not sure if that includes refrigerant charge weight..... But puts you in the ballpark anyways

Demented I can not find a call out any where for beams
 
The 38APD08055-10020 unit was replaced January 2019. Not sure with what, but it was bigger. I can find no permits in regards to this. Only a few emails between building officials and police about a road closure, and it's an odd conversation to have if there were permits.

Edit: Conversation was the incorrect phrasing. Odd question to ask if it were permitted.
 
acinstall_nk7bhp.png
 
#Demented, My memory ain't what it used to be.. I just found info I now remember seeing say a week ago?
Here is the replacement concrete beam drawing.
Question for my feeble mind is how do you support the 2003 temporary steel beam that was left in 2003, with COLUMNS, while you lift it slightly to remove old concrete beam, and build formwork to pour new beam, and hopefully reinforce it?

I can see crane lifting say steel beam perhaps, and another crane say lifting old concrete beam off roof, but that temporary steel structure has to be supported while you are forming, reinforcing and pouring new beam that rests on top of columns. And surely they wait at least 7 days if not 28 days before loading new concrete beam???

Edit so new concrete beam weights 5300 lbs or so? Which is way heavier than the 1/2 load it is supporting? Does this make any sense? Why not use Steel and just paint it often? A lot faster in and out, and less expensive too... And neither steel or concrete seem to fair well on reclaimed Ocean?
Concbm_tbu5gb.jpg
 
@Thermopile If you scroll up I posted some stuff with the permitting of the repair. As much as I can find regarding that whole section.

As for the concrete beam, it was removed in pieces by hand and bucket. Jackhammers or hammer drills likely to be used. It started as exploratory but turned into full concrete bream replacement. Small jacks could have been carried up. sections of beam. 2 little barrel jacks could do it along with scrap sections of beam or wooden blocks. This work was known to have gone on unsupervised and the slab fully poured and job completed before inspection, so I can only assume the forms were removed and the load was placed right back on the concrete beam, under the assumption the temporary support beam would be enough. This repair work was done by the same crew that did the balcony and column repairs.

It is all very confusing.

Edit: 4800lb beam assuming they just left out all the rebar.
 
Demented, I understand two bottle jacks and some wood cribbing you can do it, and I guess no issue to put load directly on slab and not over columns them self. Growing up my dad owned a trailer park, and I am far better at blocking a trailer up than I want to be.
I was just thinking no concern for shifting load onto jacks without supporting down 3 floors???

Steel temporary beam does not look long enough to provide end support with a couple of bottle jacks and cribbing.....

Barrel Jacks are Bottle Jacks in my State.........
 
Let's lift 1/2 of platform lift with no wheel chocks, flat bed too close behind fork lift, and I am sure I am missing more...

So this ingenious idea also does a 4 piece W14x43 so that each section can be hand trucked up the elevator to the roof, rather than having to have a crane show up to put a proper steel beam? Beam is 25 foot long, so perhaps a special order length?? And of course welding on roof, if they actually did that at joints. Joints just increase rusting versus continuous beam...
 
It appears the original beam in that location would have been a BM38. Why would it increase to 12x24, and how? Did they concrete around the original? If you did that, you wouldn't have to lift the steel beam and you could easily pour it from the top.
bm38_zadneh.png
 
> The Penthouse & 12th-10th floors collapsed first and slowly floor by floor to floor 8

The security video shows those floors falling from below, doesn't it? You can see down as far as about 8 or 9 and the upper part of the facade is intact. And there's still the question of why no-one (especially 111, in this theory the dropped items land right next to their terrace window) reported anything falling from above.

And although I can see that shoddy engineering supporting that AC block could let it drop onto the roof or rest on structures not designed for it, I don't see how that could cause a major failure. The columns are under much lower load up at the top of the building. I could understand a slab driven top down failure caused by that heavy unit dropping onto the roof and then the PH dropping onto floor 12 and so on, but that's not what we see from outside.
 
PH5 houses columns D2 and D4.
nopermit_harxro.png

revision_ddjb57.png


Permit 21-181 has not been released.


This are is starting to look a whole lot more suspect than the pool deck. Loads of unpermitted work and major structural repairs in a highly concentrated area.
 
If it was just unpermitted work that caused that building to fall down, there wouldn't be a condo standing for miles.

I dunno. Could be wrong. Maybe this one was just a convergence of incredible incompetence unlikely ever to happen again.


spsalso
 
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