SF tower settlement 25

[hokie66]

lillliput,

Suffice it to say that there are a lot of possibilities. You won't find any definite answers here, and as discussed above, this will take years to resolve, if ever.

 

[oldestguy]

OK so we joked a little. However, does anyone have any CORRECT history of construction as well as an on-going record of measurements? Can we learn from any mistakes? Maybe.

 

[msquared48]

What makes you think I was joking?

Mike McCann, PE, SE (WA)

 

[fattdad]

there is no negligence by running piles to dense sand rather than bedrock. If each pile can develop the capacity it needs in the dense sand, where's the problem? There is a problem designing for some capacity and not documenting that the installed pile developed that capacity. There is also a problem not knowing the performance details of the piles. I mean if the piles remain good against failure, but they required 16 inches of settlement to develop their full capacity, that's a serviceability problem.

I can't believe 16 inches of settlement! I mean are the water/sewer connections failed?

f-d

ípapß gordo ainÆt no madre flaca!

 

[hokie66]

Why do you question the 16" settlement quoted, fattdad? I would think if this was not factful, there would have been a denial by now.

Yes, the service connections would present big problems, as would probably a lot of other relationships with the surrounding ground level surfaces.

In a situation like this, servioeability/settlement failure is overriding, and strength is of less importance. Too much settlement can indeed be evidence of negligence. That remains to be determined in this case.

 

[marty007]

I wonder if the parking garage entrance is near the maximum settlement area. It would make the perfect home for Evel Knievel.

 

[JohnRBaker]

To say nothing of raising havoc, in one fashion or another, with the handicap accessibility.

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

 

[racookpe1978]

9 Aug 16 16:59
Somewhat of a side note, but...

Could the right "seismic event" cause liquifaction of the underlying sand and cause a rapid decline in building stability, or are the underlying ground specifics not appropriate for such a reaction?

In just the last moderate SFO earthquake in 1989, Mission District buildings on fill dirt in the bay DID collapse and sink into the ground just for that cause. Saw videos of the entire first floor below ground.

 

[fattdad]

I don't question the settlement at all! I was just saying the dense sand could be safe for foundation support (i.e., strong enough), but some other layer may settle. So, how did the original design consider settlement if the foundation bears on soil rather than rock? Were the soil layers and their properties estimated (I'd doubt it)? So, it'd be likely that somebody studied the strength and compressibility of the dense sand, the soil above (mud?) and the soil/rock below. I just could not claim because the foundation did not go to rock there was some negligence.

Sorry to confuse. . .

f-d

ípapß gordo ainÆt no madre flaca!

 

[JStephen]

Just a stir-the-pot article, no real news:

http://www.pressdemocrat.com/home/6370566-186/leaning-san-francisco-tower-seen?artslide=0

My favorite line,
"said Dodson, an attorney who has helped organize homeowners lawsuits. 'I can tell you that satellite data is way more accurate that digging in the dirt.'" Translation: We don't need no stinkin' surveyors, we got Google maps!"

 

[msquared48]

Heck of a project for "Slabjack".

Mike McCann, PE, SE (WA)

 

[BigInch]

Dodson is going to be in for a few big surprises over the coming years.

 

[JedClampett]

This is the perfect storm:
[ul]
[li]Condominium[/li]
[li]Flaws that might be huge or not.[/li]
[li]Extremely rich entitled tenants.[/li]
[li][/li]
[/ul]Many lawyers are going to get very rich.

 

[boo1]

article at:

https://www.bloomberg.com/news/arti...-francisco-s-tilting-sinking-millennium-tower

 

[JAE]

boo1 - that is a good article and fairly described all the challenges, both engineering-wise and in terms of the legal issues.



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[dik]

great... and I'd be somewhat concerned about the hairline cracks in the basement...

Dik

 

[JAE]

Hairline cracks not a problem...not at all....

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[hokie66]

Thick hairs, those.

 

[LionelHutz]

Are we going to be making posts about this building in this thread in the future?

http://www.eng-tips.com/viewthread.cfm?qid=420273

 

[dik]

LionelHutz:

Yes

Dik