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

[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

SF Charlie
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[SFCharlie]

containing the four images shown in my last submission.

Please find attached:
Photo 4 from_MarkBob2's_last_submission un-cropped .png

SF Charlie
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[Demented]

@Santos81
No, this is not Danny.

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

 

[Eufalconimorph]

FOR SHITS & GIGGLES ONLY, NOT SERIOUS

Upscaled images 1-3 from the MarkBoB2's post in Topaz Gigapixel AI by 4x. Totally bullshit for anything serious, since it's whatever the hell hallucination the machine learning model drew in. But no upscaling algorithm can add detail that isn't there in the source and still be accurate to reality, so this is no worse than PowerPoint's scaling (probably Lanczos resampling).

https://imgur.com/a/ahMb5vH

https://i.imgur.com/hrY03hh.jpeg

https://i.imgur.com/ELBnjTH.jpeg

https://i.imgur.com/CzKnMUe.jpeg

Edit: broke out the individual image links since Imgur doesn't make it that obvious.

 

[AusG]

Sadly that station is not present on the NOAA database I found. It may have tides, but not all the reference datums recorded. Haulover also has insufficient data. No matter, we get the idea. At high water and "higher high water", this thing had wet feet, but not all the time. Posted as image to preserve tabulation. All numbers in feet.

Link to NOAA
Link

 

[MaudSTL]

Indian Creek Golf Course ICWW Station ID #8723094 is the nearest appropriate location.

Ironically I first used Biscayne Creek but then thought twice and switched to the Atlantic side Miami Beach 8723170. I am still not clear on why we want the other side, but will be glad to change out the images.

 

[CE3527]

if the root cause is related to some type of sinkhole, pile failure, subsidence, foundation collapse, etc. it should be fairly easy to rule in or out. Either the remnants of the garage column bases were there or they weren't during the cleanup. Based on the few grainy photos available, I haven't seen any evidence of a foundation issue in the photos but only so much can be seen in them. The people on the ground should have seen it. Either there is nothing there to support foundation failure or there is, and they havent made it public.

 

[missstructures]

Pictures of almost clear site, basement slab appears to be pretty intact...

https://twitter.com/senpizzo/status/1417657635709636613?s=19

 

[AusG]

and
Agreed. In the one image we have seen of the garage floor dry the column bases are at least visible, although some more strongly represented than others. No holes anyway, and the floor looks undeformed to general observation. Sinkholes (etc) not making a strong case for themselves right now. My interest was to see if hydrostatic pressure was relevant, or if the discussion of saltwater was confined to corrosion issues.

 

[Auri]

I don't get the purpose of the Powerpoint. Wouldn't it be better to interview all the workers/inspectors up there in the 1-2 weeks preceding failure, ask them how many people were up there, what were they doing, what equipment they brought up/down, and cross check with notes, communications, what the security guard(s) remember?

That way one could tell which AC units were replaced, or any davits/weights installed for stucco work. To conclude any of that was causative of collapse is yet another matter - well that's where engineers would begin.

Staring at magnified images of post-demolition rubble means we're really reaching for straws. Making out arbitrary shapes to suggest they built hanging platforms while replacing AC's seems downright silly. Anything that separated from the roof during/after the fall landed at plaza level, likely mixing with anything that could have fallen ahead of the roof, right? The 87 Park video clearly shows the mid-section roof angling toward the viewer as the building south facade fell first, after which the two other sections (mainly the north) had the chance to spill debris over that.

 

[Santos81]

I am still not clear on why we want the other side, but will be glad to change out the images

There is a continuous bulkhead and dyke N-S along the eastern hardpack boundary from Haulover Inlet to South Pointe Park. In addition every structure along this path has an additional bulkhead placed 120’ west of this. The elevation is higher on the east side of A1A than on the west. Along the East shore of Biscayne Bay, the elevation is lower by several feet, the interior bulkhead is not continuous, private sea walls are inconsistent, and the storm water discharges are located there. Despite efforts to secure these with anti-return valves and pump stations, sea water is still entering many of these due to elevations that are no longer sufficient and frequent equipment failure.

Geography adds an additional problem. In the camera feed, we can see the tidewater entering from the west and moving east; the opposite direction we’d expect based on lunar movement. Biscayne Bay is very irregular when it comes to hydrodynamic flow despite what some mariners claim. CTS was due East of one of the more affected choke points.

I live on one of the manmade islands in Biscayne Bay. I’ll pull out the surveys from the new sea wall cap and bulkhead extension I did a couple years ago.

 

[AusG]

You could get a gig on NCIS mate!

 

[dik]

News...

https://www.ctvnews.ca/world/judge-...r-victims-in-florida-condo-collapse-1.5518267

"As the remaining rubble from the collapse of a 12-story oceanfront condominium was cleared away Wednesday, a Florida judge said victims and families who suffered losses will get a minimum of US$150 million in compensation initially.

That sum includes about US$50 million in insurance on the Champlain Towers South building and at least $100 million in proceeds from the sale of the Surfside property where the structure once stood, Miami-Dade Circuit Judge Michael Hanzman said at a hearing.

"The court's concern has always been the victims here," the judge said, adding that the group includes visitors and renters, not just condo owners. "Their rights will be protected.""


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

-Dik

 

[Auri]

https://www.nbcmiami.com/news/local...far-from-collapse-site-deemed-unsafe/2500171/

Another condo evacuation over questionable garage columns. Three-story, built 70 years ago, 93rd & Collins... Evacuation wasn't mandatory; residents are just going ahead with it. The unresolved mystery of Champlain South - likely to persist for quite some time - is serving as a potent wake-up call to get people to scrutinize building integrity and question what level of deterioration is acceptable.

 

[CE3527]

Interesting technical study on the effects of corrosion and resistance on punch through failure for columns and two-way flat slabs. Probably unsurprising, the study found that corrosion reduces punch through resistance, results in wider cracks, and reduces the radius of the shear punch through failure.

Link

 

[spsalso]

Another 70 year old steel reinforced concrete building on the verge of self-destruction:

https://en.wikipedia.org/wiki/The_Pentagon#/media/File:The_Pentagon,_cropped_square.png

I recommend EVERYONE evacuate the building immediately! Financial remuneration sure to follow.



spsalso

 

[Demented]

There is a continuous bulkhead and dyke N-S along the eastern hardpack boundary from Haulover Inlet to South Pointe Park. In addition every structure along this path has an additional bulkhead placed 120’ west of this. The elevation is higher on the east side of A1A than on the west. Along the East shore of Biscayne Bay, the elevation is lower by several feet, the interior bulkhead is not continuous, private sea walls are inconsistent, and the storm water discharges are located there. Despite efforts to secure these with anti-return valves and pump stations, sea water is still entering many of these due to elevations that are no longer sufficient and frequent equipment failure.

Geography adds an additional problem. In the camera feed, we can see the tidewater entering from the west and moving east; the opposite direction we’d expect based on lunar movement. Biscayne Bay is very irregular when it comes to hydrodynamic flow despite what some mariners claim. CTS was due East of one of the more affected choke points.

I live on one of the manmade islands in Biscayne Bay. I’ll pull out the surveys from the new sea wall cap and bulkhead extension I did a couple years ago.

More likely it's just been filling from the storm drains? Do you have a source for plans/maps of the drainage infrastructure? LWDD gives us an awesome interactive map for up here.

It hasn't rained all night and the tides have gone and there's no dry spots left on the slab it seems once again. Pool level remains the same, and the slab is still slowly filling.




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

 

[AusG]

The water table in the sand of course could be naturally a little higher than sea level, and be further plumped up by runoff. It looks like we are measuring it by the refilling of the garage anyway.

 

[SwinnyGG]

I have reviewed MarkBo's photos/powerpoint at length and... I'm sorry gents I just don't see those photos as evidence of, well, anything.

 

[1503-44]

I thought the opposite. More and more evidence, but of nothing.

 

[davefitz]

The regent palace condo, 3 blocks from the fallen Champlain towers, is 70 yrs old and is being evacuated voluntarily by tenants , due to structural faults. The primary owner, who already owns most units, is buying up the remaining units at reduced prices due to the amplified fears of collapse. The primary owner has plans to demolish the condo and rebuild. Overall, it shows "the market" is already functioning to replace the older condos, and the reported numbers are that over 75% of condos in the Miami area are over 30 yrs old. It is not clear where they will find sufficient structural engineers to inspect all these older units under the new inspection guidelines being developed. It looks to be a promising area for construction of replacement condos.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick