Miami Beach, Champlain Towers South apartment building collapse, Part 02 151

[dik]

thread815-484587


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

-Dik

 

[dik]

Let's play nice...

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

-Dik

 

[dik]

the problem was systemic... those little bandaids would not help, and if anything like the proposed repair were 'doomed' to failure. Putting lipstick on a pig comes to mind...

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

-Dik

 

[warrenslo]

Surveillance video seems to confirm top 4 floors over x11 stack fell first - this was where roof anchors were being installed above the penthouse. This roof area is under structural columns in the debris pile closest to the guest parking.

 

[dik]

It's the grand piano in the corner of the living room...

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

-Dik

 

[Santos81]

There weren't OSHA anchors on this structure until an unknown period shortly before collapse. They were in the process of being installed to facilitate the painting and repair of the decks and concrete walls. The permit pulled the day of the collapse was specifically for OSHA fall-protection anchors. Please see my post above for the permit info, etc.

Which anchors were replaced? They’re noted as existing in the re-cert plans, with replacement as needed after field check and necessary condition repairs to the slab performed.

 

[warrenslo]

Look who works for the roof anchor company. They also have an office in MD not too far from Morabito's office.

 

[Santos81]

Surveillance video seems to confirm top 4 floors over x11 stack fell first - this was where roof anchors were being installed above the penthouse. This roof area is under structural columns in the debris pile closest to the guest parking.

If you’re looking at the footage that’s had the beginning trimmed (the uncut version starts with a no signal white screen), key frames showing the bottom of the x11 stack between L and M falling initially are missed.

The flashes visible are the Fire Alarm Strobes illuminating.

 

[warrenslo]

Which anchors were replaced? They’re noted as existing in the re-cert plans, with replacement as needed after field check and necessary condition repairs to the slab performed.

See the 2018 Morabito Report:

 

[NOLAscience]

Lobby and pool deck would be designed for 100psf but empty most of the time

I don't care much about "most of the time". The pool deck could be filled with people when the building has a fire, could have high loads when building materials are staged there; the lobby could certainly have loads of 100 psf, at least in one span. You just never know.

I still think the calculation of the actual beach condo parking garage loads would be instructive, if not for this case, maybe for the next code revisions. Garages do not get the live load reductions that residential live load gets. That probably makes the actual/design ratios closer to the same.

 

[Vance Wiley]

In my experience the Structural gets a fee of maybe 1% to 1.5% of construction cost. You can guess at the responsibility and liability.
The realtor who sells it gets 6% each time it sells. He takes pictures and writes a glamourous description then turns it over to a title company.
What the heck was I doing in engineering?

 

[warrenslo]

If you’re looking at the footage that’s had the beginning trimmed (the uncut version starts with a no signal white screen), key frames showing the bottom of the x11 stack between L and M falling initially are missed.

Here's a slightly earlier screen cap, The top 2 floors (possibly 3) are clearly missing over the x11 stack. I think they slowly fell in pieces over several minutes prior to the main collapse causing the damage in the Tik Tok video. The Penthouse and Floor 12 had large catilever balconies across the entire unit on the x11 stack. The two white flashes are either the HVAC or electrical flashes. The prior image I shared was milliseconds later and the floors with lights on hadn't moved yet however the 10th floor light goes out by then.

 

[Santos81]

See the 2018 Morabito Report

Face mount, not post. The permit for the roof post replacement wasn’t processed until the afternoon of the 23rd after inspection. I doubt any were done in those few hours.

 

[NOLAscience]

Look who works for the roof anchor company.

That's the problem with having an unusual last name. If the engineer were Frank H Baker, we would not be sure if Harrison Baker at the anchor company was his son or not. But it was still probably a good idea for the anchors to be installed, as they are an OSHA requirement for the upcoming work.

What exactly is your theory, again, of how the installation of the anchors precipitated the building failure?

Forgive me if I drop out of this thread until Tuesday. I have fish to catch (weather permitting).

 

[dik]

There seems to be a dearth of cameras with suitable optics.

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

-Dik

 

[warrenslo]

The anchors did not exist in this Google Maps image dated 2021.

 

[NOLAscience]

The other had been moving things to a hotel for over an hour

So a resident of the building was moving a significant number of items to a hotel, just before the collapse. Why? Was the person aware of a problem?

 

[warrenslo]

What exactly is your theory, again, of how the installation of the anchors precipitated the building failure?

They installed nearly all the perimeter anchors on the cantilevered portion of the roof slab - not per the structural drawings.

 

[NOLAscience]

I'm sure many people were not concerned seeing water in the garage, it might have only concern them because they were getting their $500 shoes wet.

I've been meaning to get back to this comment with my own story.

I was working in a 50yo office park in a rather uninhabited area from 2011-2014. At some point in that time, the state resurfaced a highway and slightly improved its intersection with another highway. Based on the 1100 employees in our building and other large buildings nearby, I'd say at least 1000 cars a day used this intersection. Almost immediately after the new road surface was finished, I noticed that water was up to the level of the asphalt -- or even over the asphalt -- every day when I chose to take that route. It bugged me and bugged me, especially over the weeks when we had no rain at all. I finally emailed the local action news reporter and said, basically, "The state just spent our money to repair this road and it is not going to last very long with standing water up to the surface, even with no rain." He looked into it, and contacted someone. Driving to work a few weeks later, I saw crews cleaning out the drains. Water never pooled there again.

Why was I the only person out of 1000 per day that saw this as a problem? Most people have no clue about the damage that water causes when it is not expected.

 

[NOLAscience]

They installed nearly all the perimeter anchors on the cantilevered portion of the roof slab - not per the structural drawings.

But there was no load on the anchors last Thursday. Are you saying that the installation damaged the cantilever portion of the roof? Do we even know for sure where the anchors were installed? That would be a pretty big error on part of the anchor company, as they had drawings to guide them. Did the city building inspector note any problem with the location?

Happy Independence Day, All!

 

[dold]

Face mount, not post. The permit for the roof post replacement wasn’t processed until the afternoon of the 23rd after inspection. I doubt any were done in those few hours.

I'm not sure exactly what the permit was for, as there were clearly new anchor point 'posts' installed prior to the collapse. But I can tell you with certainty that plenty of work gets done without a permit. Maybe this most recent permit was an extension of a permit issued prior, or something to that effect?

Also, the 2018 report indicates there were no under-mount/face-mount suspension hooks (sketchy) installed under the roof level balcony covers. See my red highlights below from warrenslo's posts above. Yet they indicate (second pic) that existing under-mounted anchors be removed and the anchorbolts ground out 1.5 inches above the soffit. I'm confused.

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