Miami Beach, Champlain Towers South apartment building collapse, Part 13 44

[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
Miami Beach, Champlain Towers South apartment building collapse, Part 08
Miami Beach, Champlain Towers South apartment building collapse, Part 09
Miami Beach, Champlain Towers South apartment building collapse, Part 10
Miami Beach, Champlain Towers South apartment building collapse, Part 11
Miami Beach, Champlain Towers South apartment building collapse, Part 12


SF Charlie
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[SFCharlie]

This one has both rounded column and dropped slab preserved

I like your photo choice. It is late enough at night that I confused dropped slab with slab drop, sorry
Please use your favorite drawing tool to circle or outline the items mentioned above, so we all know we are talking about the same thing.
Thanks

 

[AusG]

and I had a nice PPT all ready to go...

Aggregate

I too believe the concrete will prove to be sub spec, but I believe aggregate is there, but made of pale grey soft local limestone: so almost no colour or mechanical contrast to the concrete. I may be naïve but I find it difficult to see a concrete company turning up with a sand slurry and not one responsible individual caring.

 

[CE3527]

An opinion piece from a lawyer, and a foundation company describing soil types in Florida are not the solid evidence that supports your claims.

That lawyer seems to be presenting themselves as an expert in geotechnical engineering and offering theories which imply some degree of certainty, with no citations to actual experts in the field.

"Absent an act of terrorism, the most likely cause of the building’s collapse was either a construction defect or a foundation failure likely caused by soil liquefaction."

They've skipped over more prominent theories put forth by experts so far, i.e. design defects and structural degradation over time.

Maybe it doesn't rise to a level of professional misconduct, but nobody should view this as a legitimate source.

 

[SFCharlie]

Quote (SFCharlie)
and I had a nice PPT all ready to go...

Go for it! I'll race ya'
I already loaded that photo into PPT and now I'm trying to blowup the cap of each column.
I'm so tired, I'm pretty sure I won't finish tonight.


SF Charlie
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[Nukeman948]

That lawyer seems to be presenting themselves as an expert in geotechnical engineering and offering theories which imply some degree of certainty, with no citations to actual experts in the field.

Unscrupulous people often post current news items to get more people to visit their site. The more traffic they get equals more name recognition for these lawyers which pays off as more business over time.

 

[Phil1934]

https://www.miamiherald.com/news/local/community/miami-dade/miami-beach/article254082008.html

 

[MaudSTL]

In Contractor for fallen Surfside condo later lost license amid fraud, negligence claims, the Miami Herald goes after one of the three contractors who built CTS. The first one quit when the penthouse was added, the second one (whose poor business practices are detailed in this piece) lasted only three months, and the last one finished up the job. All three are deceased.

 

[MaudSTL]

Building Audits After Surfside Collapse Uncover Unsafe Structures, Violations When our building falls down, we want the government to have protected us and will blame it for having failed to do that. When our building has not fallen down, we want the government to stay out of our business, and drag out repairs for years and years.

 

[spsalso]

The Miami Herald article sure is interesting.

Reading between the lines, the last two contractors were window dressing for a non-contractor to run the job. That is my opinion. It certainly doesn't appear they were hired based on their record in the field.

NOT reading between the lines, I see that the permit fee was $13,121 (about $43,000 in today's money).

As I've mentioned before, since the Surfside part-time building inspector wasn't up to the task, that money could have been used to hire an outside inspector. I kinda think it SHOULD have. And I kinda wonder why it wasn't done.



spsalso

 

[MaudSTL]

…since the Surfside part-time building inspector wasn't up to the task, that money could have been used to hire an outside inspector. I kinda think it SHOULD have. And I kinda wonder why it wasn't done.

To serve the greater good, the Miami Herald is helping to build the criminal negligence case against the Town of Surfside. The smaller the entity to take the fall, the more the Florida real estate market is protected. The Miami Herald has already done pieces on the Bad Developer, the Bad Architect, the Bad Engineer, the Bad Building Inspector, and now the Bad Contractor. It is becoming more clear that only one entity could have protected public safety, and that’s the Town of Surfside. I think that next they’re going to go hard against Ross Prieto and the town management.

 

[Red Corona]

Re liquefaction or other ground issues: There were some reasonable hypotheses in this area, but as the critical columns in the pool deck collapse appear to be intact, and the basement slab looked in good condition after the clearance, I think we can take any foundation-based theory off the table.

Re the concrete being apparently sub spec or degraded: why, then, is nobody scared about CTN? It was built pretty much at the same time by the same people, so if the worry is the structural elements of the building, you'd expect that to be true there, too (and in fact in every 1970s/80s reinforced concrete structure in the area ...).

> If this were the case, there should have been those bars still connecting each "side" of the slab. They would now be found surrounding the bottom of the columns.

All the pool deck columns, and the ones under the surface parking like @AusG's photo, had their slab around the base. I'm sure NIST had a good look at those bits of slab before clearing the site.

 

[Debirlfan]

Re the concrete being apparently sub spec or degraded: why, then, is nobody scared about CTN? It was built pretty much at the same time by the same people, so if the worry is the structural elements of the building, you'd expect that to be true there, too (and in fact in every 1970s/80s reinforced concrete structure in the area ...).

Maybe people should be worried.

Beyond that, why was this particular building the one that failed? Did the crane accident during construction cause hidden damage and/or budget and time delay issues that resulted in more corners being cut? Were things learned in the construction of this building that were applied to subsequent buildings with regard to column size, etc? Did some event (construction next door, revisions to units, etc) push this building over the edge? Was maintenance just that shoddy?

 

[SFCharlie]

ACI friends and colleagues,

Today, I am writing you to share the disappointing news that the ACI Concrete Convention planned for October 17-21 will transition from a hybrid event to a fully virtual one. With the rise in COVID-19 cases, it has become increasingly clear that a fully virtual ACI Concrete Convention will be safest for ACI members, attendees, and staff.

Just a few short months ago, we were excited at the opportunity to see each other again in Atlanta, GA – I know that I was, and I’m sure that you were, too. But rest assured that we are channeling that collective excitement into making the ACI Concrete Convention the most productive and best virtual event it can be. The ACI staff is now working with the ACI Georgia Chapter, convention sponsors, session speakers, and committee leaders to transition the event. While all details are not yet finalized, know that ACI will still be hosting committee meetings, informative technical/educational sessions, social activities, sponsor demos, celebrations, and the other activities that make our conventions special – albeit in a fully virtual format.

If you’ve already registered and/or reserved your hotel room, ACI will confirm if any action is needed and be in contact soon. ACI suggests that you cancel your travel plans. If you haven’t yet registered, now is the perfect time to register for the virtual ACI Concrete Convention (and take this opportunity to invite a friend or colleague to join you, too).

Thomas Concrete, Baker Concrete Construction, ConSeal, and 50+ additional companies and organizations have signed on as sponsors – I sincerely encourage you to view all sponsors, thank them, and support them as you are able.

Questions can be directed to conventions@concrete.org. Additional details will be posted to the ACI website when finalized, and we’ll be back in contact soon.

Sincerely,
Cary Kopczynski, PE, SE, FACI, FPTI
ACI President

SF Charlie
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[Jeff Ostroff]

I just uploaded my video this evening where I drove over to Champlain Towers North who has the same garage, next door to the collapse site last week, and recreated the tourist video in the daytime and even got cars coming out of the garage and the gate opening up so we could see all of the columns very well lit and back to the back wall to show like wherre the debris field was in the tourist video, which was shot 5 minutes before the condo collapsed. Here is a screenshot I made showing the columns:
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[AutisticBez]

Jeff M11.1 is rotated 90 degrees in north building. This column is 12 by 16. At south the wider 16 inches would be facing the ramp. In north the 12 is facing the ramp.

Technically this would require a much higher speed of vehicle impact to bottom shear the north M11.1 column. All the 11.1 columns are rotated in the north building.

Did they learn something in the process of building south?

 

[spsalso]

Easier to park if you rotate the columns?


spsalso

 

[Jeff Ostroff]

There must have been other reasons to rotate those columns, you only gain 4", not a big difference in parking

 

[hokie66]

Jeff,

Tell that to the folks who write the regulations on size of parking spaces. Depending on where you are, you can be off by an inch and fail.

 

[AusG]

Which failed first?

Well it can't be "22" at CTN, (which is "27" at CTS), because it was still standing in the tik tok video.

 

[Optical98]

Surfside mayor gives tenants 45 days to leave his building in Miami Beach

https://www.local10.com/news/local/...nts-45-days-to-leave-building-in-miami-beach/