Miami Beach, Champlain Towers South apartment building collapse, Part 12 60

[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

SF Charlie
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[gonefishing2]

Let's see how good Demented's Math skills are. Question is how many Harbor Freight Winches will it take to right the leaning Millennium Tower on the other Coast? We were leaning 17" before the 100M repair started in May, but now we are leaning 22"?

Perhaps SFCharlie can come up with a 'do-dad' fix? EDIT: Perhaps a series of Flying Buttresses like the old Cathedral's?

Next Question: Who wants to live in a High Rise on either Coast?

Link to NBC Bay Area article:

https://www.nbcbayarea.com/investig...partial-work-stoppage-documents-show/2641422/

 

[Optical98]

Millennium Tower fix = 2 do-dads and a tar kettle in the basement~

 

[SFCharlie]

Millennium Tower sank another inch this past month.

I guess it is not an Engineering Failure nor Disaster yet, but I'm surprised I can't find a thread for the "Millennium Tower"

SF Charlie
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[SFCharlie]

how many Harbor Freight Winches will it take to right the leaning Millennium Tower on the other Coast?

When the new span of the bay bridge was built, they brought in the "Left Coast Lift" (real name, I believe), the largest floating crane west of the Mississippi...
(that will take a while, but I'll get on it)
SFCharlie for one

SF Charlie
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[apper.42]

I cant't find tread for Millennium Tower

Its under SF Tower Settlement Part II - Key word here is "yet" but engineers are working on making it worse as we speak. Unbelievable!!

 

[AusG]

Now the question - about aggregates in Miami.

There is aggregate...

but as you observe it looks barely harder than the cement, and is pale coloured presumably limestone.

 

[dik]

apper: Catch the link...

https://www.nbcbayarea.com/investig...x-of-san-franciscos-millennium-tower/2639941/

as far as aggregates go... if there are chlorides in it, it can reduce the passivity of the concrete (not cement, that's the pozzolan used to make concrete) and reduce the ability to resist corrosion.

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

-Dik

 

[SFCharlie]

Sorry for the diversion but a promise is a promise

There, that wasn't so hard...
Now back to the aggregate

SF Charlie
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[AusG]

SF Millenium Tower just needs they do what they are already doing, but harder and on the other side to even it up.

 

[spsalso]

What you're seeing with Millennium Towers is the first phase:

Pound a whole buncha pilings in, all the way to bedrock.

IF the building tilts too much during the first phase, bungee cords are used as safety devices, and are tied around that cucumber shaped building nearby.

Phase two involves a whole lot of hydraulic jacks. One is placed above each pile, and the jacks lift the building back up to vertical. There will be a guy (paid double time, by the way) up on top with a 24" level. He will be in constant communication with management.

Phase two point one is removal of the bungee cords. Great care will be taken to avoid them "snapping" out a window or three on adjacent buildings.

Phase three is filling the whole cavity where the hydraulic jacks are with, yes, CONCRETE.

Phase four is the after-party, which will take place in the East Bay. Just in case.


spsalso

 

[SFCharlie]

Do-Da Do-Da and now...
Back to the aggregate in Miami (I know the group trying to build the new Panama Canal locks ran into a problem. They were going to use the rock quarried out of the lock site, but there was an unrecognized fault running through it and the rock was too fractured to meet spec, so they had to find a new quarry...)


SF Charlie
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[SFCharlie]

From the Miami Herald > AP > Miami Herald article...

“The white color just stuns me,” Aghayere said. Instead of seeing aggregate material mixed into the concrete, “it’s just homogenous,” he said, a likely indication of saltwater damage.

as far as aggregates go... if there are chlorides in it, it can reduce the passivity of the concrete

Saltwater corrosion of the aggregate or just "we don't need no stinkin' aggregate"


SF Charlie
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[apper.42]

Back to Millennium Tower for just a bit. If you want to reduce settlement do not drill 36" dia. piles through the unconsolidated marine clays and give a path to release the excess pore water pressure from the 10' thick matt sitting on them and thereby increase the settlement instead of slowing it down. I'm no geologist but my god you don't have to be to know this was a very bad idea.

 

[Vance Wiley]

CTS is not the first one in Florida - -
While searching for a copy of ACI 318-77 I found this:

Source:

https://www.concrete.org/publications/internationalconcreteabstractsportal.aspx?m=details&i=9056

Title: Cause of the Condominium Collapse in Cocoa Beach, Florida

Author(s): H. S. Lew, N. J. Carino and S. G. Fattal

Publication: Concrete International

Volume: 4

Issue: 8

Appears on pages(s): 64-73

Keywords: buildings; concrete construction; failure; flat concrete plates; punching shear; shear strength; strength; structural analysis.

Date: 8/1/1982

Abstract:
Gives the results of an investigation into the collapse of a five-story, flat-plate condominium building in Cocoa Beach, Fla. The collapse occurred on March 27, 1981, while the casting of the roof slab was in progress. Eleven workers were killed and 23 were injured. The investigators conducted on-site inspections, made laboratory tests, and made analytical studies. It was concluded that the most probable cause of the collapse was inadequate punching shear capacity in the fifth-floor slab to resist imposed construction loads. The analysis indicated that punching shear stresses at many slab/column connections were close to the ultimate capacity specified by the Code (ACI 318-77). Consequently, it was Concluded that a punching shear failure at a heavily stressed location triggered a succession of failures at other locations, resulting in the downward collapse of the entire structure.
Dejavu all over again?

 

[AusG]

My money is on bad aggregate in worse concrete, with too little of it around threadbare steel, in not enough beams and shear walls. Add weather and poor maintenance and this thing is a mudpie with nice curtains and a pool. And that is just from listening to y'all put it all together.

 

[12345abc6ttyui67]

There is a separate thread for Millenium Towers, please keep any comments regarding that topic over there instead.

[link]https://www.eng-tips.com/viewthread.cfm?qid=470048[/url]

 

[arbitraria]

@VanceWiley - I believe somewhere in the previous threads someone posted a link to the federal investigation report on the Cocoa Beach collapse. I also found this article from the day after CTS came down:

Structural engineer sees similarity in deadly South Florida, 1981 Cocoa Beach collapses

"...the 1981 Cocoa Beach collapse inspired a law that required structural engineers and inspectors...to undergo a qualification program to 'enhance the quality control and inspection during construction of 'threshold buildings.' ' Such structures include those over three stories or 50 feet or built for more than 500 people."

Unfortunately, both of these buildings were under construction at the same time, so the additional regulations came too late for CTS. It would also appear that those lessons may well have been lost on subsequent inspectors over the years, if Surfside's questionable repair approvals are any indication.

 

[Demented]

Let's see how good Demented's Math skills are. Question is how many Harbor Freight Winches will it take to right the leaning Millennium Tower on the other Coast? We were leaning 17" before the 100M repair started in May, but now we are leaning 22"?

You know damn well they'll burn out straight out of the box and burn the place down. I don't think China was able to produce aluminum when my ref books were printed. Anyone have strength data for pot aluminum?

I like spsalso's plan. He's just missing some whistles and hand gestures.

Edit:
The local aggrigate mines in the area are Limestone mines, especially if it came from Cemex.

 

[Demented]

@arbitraria
@Vance Wiley

Here's that link again

https://www.govinfo.gov/content/pkg...VPUB-C13-c3d64fd6d7663600a6e3a147919af0a1.pdf

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

 

[gonefishing2]

There is a separate thread for Millenium Towers, please keep any comments regarding that topic over there instead.

https://www.eng-tips.com/viewthread.cfm?qid=470048

Be careful what you ask for? Are you sure you want all the "do-da's" and powerpoint guru's to invade a forum that has been lean, mean and focused?

Quote (Thermopile)

Now that I have been exposed, I guess I will have to reinvent myself again. Perhaps this time Demented2 ? or perhaps SFDoDa ?

I too like spsalso's plan....They were working on wrong side………

Edit: Back to CTS Aggregate.......