Sinking San Francisco building

[NorCalAthlete]

Huh! Not sure what the joke is since that is probably what they would have to do.

Starcraft reference.


Side note - am I the only one who was like "Warcraft movie? Fuck that, I want a Starcraft movie!"

I feel like there's enough subplots and stories to fill a TV series let alone a movie.

 

[HeatXfer]

Almost this entire thread has gone off the hyperbolic deep end.

A building which leans slightly is not the same thing at all as a building which is in imminent danger of collapsing or toppling over.

+1

I'm wondering how many contributing to this thread work in industrial/commercial construction or have any construction experience besides pounding nails?

 

[afm199]

+1

I'm wondering how many contributing to this thread work in industrial/commercial construction or have any construction experience besides pounding nails?

I'm forty years in the trades.

A building like that, having subsided 16" and leaning 2" IS a problem looming. It is NOT a joke. It is not a minor detail.

 

[Ogier le Danois]

Lean like a Cholo

 

[Johndicezx9]

Diggin' the scene with a gangsta lean?

 

[VicTim]

I've been a carpenter for over 30 years. I'm just loving this thread. I was a Union Carpenter early in my career and did layout on large projects in the City. Many lawyers will get rich over this problem. I'm looking forward to following this story for the next several years. No telling how many lawsuits will come over this one. A good time to be a lawyer.

 

[bruceflinch]

Almost this entire thread has gone off the hyperbolic deep end.

A building which leans slightly is not the same thing at all as a building which is in imminent danger of collapsing or toppling over.

Yes, look at the Tower of Pisa. Couple hundred years of leaning.

645 feet vs 183 feet
14,500 metric tons versus 14,000 pounds per square foot (Can't find weight anywhere, nor square footage of footprint) probably at least 20 times heavier, maybe much more.
Soft soil versus landfill.
Apples and oranges.

You are apples & oranges.
We were talking only of the leaning aspect, not what caused it.

It's not the structure that is at risk here, it's the foundation and the lack of piling reaching down to bedrock. With the lever of a tall heavy building being swayed by a large earthquake, the insufficient pilings could prove to be a catastrophic mistake.

Uh... The foundation is the substructure, and above ground is the superstructure. So you think if the foundation fails the superstructure will still be ok?

 

[Climber]

You are apples & oranges.
We were talking only of the leaning aspect, not what caused it.

The difference between the Leaning Tower of Pisa and the Millenium tower is that there is a lot bigger lever with a lot more weight that is going to be moving during a earthquake. We'll know in the next 10-20 years.

 

[explorin]

Someone needs to do that cliche picture of holding it up like the tower of pisa!

 

[Climber]

superstructure. So you think if the foundation fails the superstructure will still be ok?

What does the terminology have to do with the failings of the design? No matter what you call it, it still fails if it fails to support the whole structure.

 

[Blankpage]

Almost this entire thread has gone off the hyperbolic deep end.

A building which leans slightly is not the same thing at all as a building which is in imminent danger of collapsing or toppling over.

I have 20 yrs involved in building large structures from GBS oil drilling platform weighing hundreds of thousands of tons, bridges with a combined weight of single span/pier/footing combo of 16000 tons, concrete dams...
A GBS oil rig can sink inches or even feet into the seabed. No one really cares, it has no pile and tilt can be controlled with iron pellet ballast.
A large bridge span/pier/footing combo can settle 10-20 mm .
Monitoring movement and settlement was something I tracked.

This SF building settling 16" with potential of doubling that still is almost unheard of. I won't say impossible because I don't know what's happening in places like Dubai with its towers. 16" in SF is not a minor issue. Someone screwed up.

I don't doubt it could cost near $100M to fix this issue property, if they decide properly means additional pile drilled to bedrock. If that cost gets passed off to the unit owners they're looking at an average of a $1/4M in special assessment each. A lot of the units have already been discounted more than that so could be a deal for a brave investor


;

 

[bruceflinch]

I don't doubt it could cost near $100M to fix this issue property, if they decide properly means additional pile drilled to bedrock. If that cost gets passed off to the unit owners they're looking at an average of a $1/4M in special assessment each. A lot of the units have already been discounted more than that so could be a deal for a brave investor


;

BARF Group Buy?

 

[Climber]

I have 20 yrs involved in building large structures from GBS oil drilling platform weighing hundreds of thousands of tons, bridges with a combined weight of single span/pier/footing combo of 16000 tons, concrete dams...

Is it possible to drive piles down from inside an existing structure?
I know that technically, it's possible, but is it feasible? How would you then support the structure with each new pile driven down?

Seems like an interesting engineering puzzle, but not one I'd want to have to implement, seems like it would be very tedious going.

 

[Cycle61]

BARF Group Buy?

I'd toss a few bucks in on that.

 

[Blankpage]

Is it possible to drive piles down from inside an existing structure?
I know that technically, it's possible, but is it feasible? How would you then support the structure with each new pile driven down?

Seems like an interesting engineering puzzle, but not one I'd want to have to implement, seems like it would be very tedious going.

This is a massive one but they come smaller than this also. Either a rotating or a oscillating pile drilling machine. You don't have to drive them, you slowly drill them into the earth and keep attaching another section as they get deeper. Sucking out dirt as it's drilling.
Perhaps a smaller one could be setup in the basement if given a couple of floors of head room. And depending on the space around the perimeter of the building who knows but it may even be possible to extend the foundation and add pile around the perimeter without having to go inside.

I'm not a pile driver but I've been around all sorts of heavy duty pile operations.

 

[DTM74]

This is a massive one but they come smaller than this also. Either a rotating or a oscillating pile drilling machine. You don't have to drive them, you slowly drill them into the earth and keep attaching another section as they get deeper. Sucking out dirt as it's drilling.
Perhaps a smaller one could be setup in the basement if given a couple of floors of head room. And depending on the space around the perimeter of the building who knows but it may even be possible to extend the foundation and add pile around the perimeter without having to go inside.

I'm not a pile driver but I've been around all sorts of heavy duty pile operations.

Nicholson Construction did this for the Mandalay Bay Casino that was settling. They drilled over 500 Micropiles from inside the structure.

Great picture, Blankpage! I was on that project (Benicia Bridge). I used to work for Malcolm Drilling.

 

[bruceflinch]

Nice Pic BP!

 

[Blankpage]

Nicholson Construction did this for the Mandalay Bay Casino that was settling. They drilled over 500 Micropiles from inside the structure.

Great picture, Blankpage! I was on that project (Benicia Bridge). I used to work for Malcolm Drilling.

Was it 3 footings that Malcolm had to drill pile for in Benicia, 9 pile per footing?
Drilling pile was never part of the initial contract. Malcolm was contracted when pile couldn't be driven to tip elev using their pile hammer because of harder than expected ground.
I'm not sure the exact numbers but the additional cost to the Benicia bridge of contracting Malcolm was huge, over $100M?

Here's a smaller oscillator for low clearance issues.

 

[Climber]

Thanks for pictures, they are very cool!

 

[DTM74]

Was it 3 footings that Malcolm had to drill pile for in Benicia, 9 pile per footing?
Drilling pile was never part of the initial contract. Malcolm was contracted when pile couldn't be driven to tip elev using their pile hammer because of harder than expected ground.
I'm not sure the exact numbers but the additional cost to the Benicia bridge of contracting Malcolm was huge, over $100M?

Here's a smaller oscillator for low clearance issues.

All together there was 17 Bents/Footing that were on the project (for the bridge). There were 8 piles per footing, IIRC. The piles were always part of the contract. Kiewit was the GC and they initially began to drill the piles using their reverse oscillation method. Basically, it's an open hole method that works good in competent material (they actually did a few Bents with this method). But when they got to the deeper shafts, and the claystone/siltstone turned to weathered crap, they couldn't keep the hole open and had caving conditions. So they had to backfill the shafts and come up with a new game plan.

So after wasting alot of time and money. Caltrans pretty much said that the shafts had to be cased down to tip. Being that Malcolm was the only driller with the equipment capable to do such a job, they made a lot of money. It was all T&M...I think it was around a $40M dollar job. It was a pretty impressive job.

The 3 Bents you may be thinking of might have been the land footings, which Malcolm did on the south side, I believe in early 2002...prior to me coming on board.