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Miami Beach, Champlain Towers South apartment building collapse 151

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I see on sheet 96 of 336 (the mixed up plan sets) shows three area drains (referred to as “DD”, Deck Drains?) are indicated in the sloped area surrounding the pool. And the pool is a simple rectangle, no stairs shown. But on later sheets the drains don’t show. The 2018 report indicates that the lack of slope (and drains?) was instrumental in the damage to the deck. However, the 89 sheet set of proposed drawings, Phase IIC, done buy, in part, the same firm that bears name of the engineer that did the 2918 report does not seem to rectify the “flatness” of the area around the pool.
Where are Phase IA, XX, XXX etc plans? Where are the Phase IIA Plans.
I may have used a golf club to “sound” the walls and ceiling, but don’t think I would have mentioned the club, only the results in the report. Rather brings up an image of the inspector wearing golf clothes with white shoes.
Steve
 
Stevewag, sheet S2C-1.1 shows the overlay to correct deck drainage.
Screenshot_20210627-205437_suzn2y.png
 
Former Building Superintendent 1995-2000 mentioned salt water flooding in the parkade was a recurring problem at high tides, king tides. 1-2 feet of water "enough to make cars float around" and the two sump pumps were also problematic and could not keep up, not always working. [CBS Miami]

I looked and tide levels vary about 2-1/2' pk-pk and nothing special that day. https://tidesandcurrents.noaa.gov/map/index.html?id=8723214
Sea level trend +2.39mm/yr https://tidesandcurrents.noaa.gov/sltrends/sltrends_station.shtml?id=8723170

https://youtu.be/gh7cnY7PkLU?t=316
 
The inspector was on the roof inspecting the replacement of roof anchors.

"Jim McGuinness, who made the comment during a Town of Surfside emergency meeting, said he was on the roof to inspect work of replacing roof anchors, which are where window cleaners attach their equipment."

Modern roof anchors are tied to the structure of the building due to the 5,000# OSHA requirement. As far as I understand, there is not a way possible to meet this requirement without tying back to the building structure. The 2018 report noted to install anchors prior to commencing work, this report was flawed, the structure needed to be strong enough to add the anchors prior to adding them. Now, looking at the roof anchor permit drawings, they seem to indicate jackhammering directly into the tops of these overloaded & distressed columns from the roof (see comments above.) This was apparently happening within 14 hours of collapse. Do we know which columns were worked on? If the building was cracking for days why didn't the inspector know.

Finally, the firm that did the structural review of the building also did the structural drawings for this work, I personally think this is a conflict of interest. For example on every project I am a part of I instruct the owner to use a separate surveyor and civil, the surveyor catches a civil error every time (seriously.) They all have the young guys drawing and the older guys are hustling work barely checking. It's simple and important stuff. While we are much more precise than the hand-drawn days, CAD isn't perfect, it's only as perfect as the operator. I can recall the many times I have caught a consultant missing the thickness of a double-sided plywood shearwall. I'm thankful the framers are using Revit now and building a model themselves.

While I'm not part of a code committee yet, I have been licensed for many years, and I feel we really need to simplify the code for younger architects and engineers to understand it, or at least add pictures of what the committee means IN THE CODE! And, existing buildings need more than just a code, we need to force those who adopt IBC et al to review existing structures more often somehow. I have previously worked at an architecture office in Santa Monica where there is visible earthquake damage (cracked beams) and ownership doesn't care. They don't have to, unless they are forced to. This collapse won't be the last unless we fix the process, the boomer days of its standing don't touch it need to end.

-W
 
warrenslo said:
they seem to indicate jackhammering directly into the tops of these overloaded & distressed columns from the roof

The roof anchor drawings you reference show this detail for the "column anchors':

column_anchor_lghath.png


Two x 7/8" dia percussion drill holes @ 5" deep is not very destructive. Probably drilled with a 30lb electric percussion drill. Also, it is the ROOF LEVEL - highly unlikely the upper level columns were "overloaded and distressed".

I may have an different opinion if they were drilling a lot of holes in BASEMENT columns if there was significant visible distress, but they were not.
 
 
Other than indicating the condition of the structure, or giving you an opportunity to do remedial work, I think the roof anchors are a bit of a 'red herring'... I cannot imagine that the addition of some 5K anchors would have any overall impact on the integrity of the structure. If that sort of load is going to cause problems, then you have a more serious problem at hand. If this had any impact on the collapse, then it was just a matter of time.

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

-Dik
 
ESPN said:
When they saw dust and debris rising up over the balcony, they went out into the hall and saw two holes where the elevators once were, and saw the next-door apartment was gone. Willis ... made it down 11 flights of stairs

That suggests the collapse started before what we've seen on the CCTV footage.
 
They were in the portion of the building that did not collapse; directly adjacent to the portion that did.
 
air1970 said:
That suggests the collapse started before what we've seen on the CCTV footage.
That was my 1st thought when I 1st read the article but after I read it a 2nd time I realized that I think they were in the section of the building that didn't collapse.
 
alr1970 said:
That suggests the collapse started before what we've seen on the CCTV footage.

The combined witness statements all point to some sort of failure of the outdoor pool/patio/plaza slab prior to any major collapse involving upper levels. It's hard to say how much in advance, but it seems to be at least a minute or two, possibly as much as 15 minutes for the first signs of it. The CCTV footage from the south that's widely circulated only includes the upper collapse. It would be very interesting to carefully review the preceding hour from that camera for any movement or dust.

Some details don't quite add up, like "holes where the elevators were", since the elevator shaft is still there and appears largely intact. They are not necessarily trying to embellish or be deceptive about it, as this would be them trying to make sense of a chaotic scene with dust and destruction all around. The brain has difficulty processing what it's seeing, and constructs a memory as best it can while running on adrenalin in survival mode.

I think Willis was probably in the surviving section of the building, and the dust was from the main collapse.
 
Two hypthesises (is it Hypothesi?) I've seen here, I dont think I quite agree with.

1. The Cooling tower at the roof level was changed out. Normally these things are about 20-30 kips for a building this size and distributed over 2-4 columns. For a concrete building this size, and with typical live load reduction - its not likely the cooling tower would over load a concrete column (unless said column(s) was severely deteriorated). I dont think that is likely.

2. Roof Anchors/Fall arrest system installation. If this was a post-tensioned building and the contractor repeatedly knocked out tendons with drilling operations, I could see this being plausible. But other than localized damaged/deterioration around the anchors, they are rather non-obtrusive in the short term. One minor comment on that design, I'm sort of surprised the original engineer went with a 2 anchor design - I had assumed the 4 anchor OSHA minimum would apply to fall arrest systems.
 
Not sure if this has already been mentioned or not, but ultimately it may be a nonissue since all of the principles involved in the original development are deceased:

Developers of doomed Fla. tower were once accused of paying off officials


John R. Baker, P.E. (ret)
EX-'Product Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 

Hypotheses?

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

-Dik
 
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