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Millennium Tower is tilting, sinking

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Re: Millennium Tower is tilting, sinking

#91

Post by erdevs »

marcusgarvey wrote: post #34
erdevs wrote: post #8

Earlier quoted context omitted.

How much stock should one put in that declaration of safety? It is from an "independent" analysis... but who paid the analysts? Or, suppose absolute freedom from bias... how many times have expert opinions of safety been wrong in the face of mother nature. Picture Fukushima. The risks in a tilting building are many. From a market value standpoint, homeowner value has already been destroyed simply by perception. If re…

>Taxpayers may well be pulled into the fray and suffer as well in these situations. How might this happen - do you mean via the Transbay Dev.?

Yes, that for sure is mentioned as a distinct possibility. Sometimes in such matters the city can also be sued for approving plans if they are subsequently found to be faulty or inadequate as well. And if there is any other construction going on nearby besides this Transbay Terminal that was mentioned, that could be called into question as well.

Re: Millennium Tower is tilting, sinking

#93

Post by omegaworks »

JosephHatfield wrote: post #61
wahern wrote: post #29

Earlier quoted context omitted.

I live in the Outer Richmond district of San Francisco, which was built on sand dunes. Most houses in my neighborhood were built in the 1920s and 1930s, +/- a decade. I was told by a contractor that it's extremely common for houses to have shifted considerably, sometimes by several feet. Mine certainly has, though not nearly that bad. Most of the houses are built on concrete foundation walls that go about 3 feet into…

The city is currently requiring many owners of soft story buildings in the Outer Richmond district to pay for seismic refitting.

...And allowing them to pass on 100% of the cost to their renters.

Re: Millennium Tower is tilting, sinking

#94

Post by spikels »

capkutay wrote: post #22
philip1209 wrote: post #10

"To cut costs, Millennium did not drill piles to bedrock." What are the implications for earthquake safety?

Because Millennium is on reclaimed land, they cannot determine whether or not they have drilled into bedrock. They drill into what's called the 'point of refusal'; a point where they can no longer drill deeper. Whether this is bedrock or even stable soil is somewhat vague.

Almost nothing in this comment is accurate:

- You CAN determine the type of rock you are drilling through as well as it's relevant characteristics. Pieces of the material are brought to the surface with the drilling mud and instruments are put down the hole.

- Builders DO NOT just stop drilling when their drill won't drill no further. (This made me laugh!) There is testing, design, design review, more testing during construction, more design review and perhaps modification based on conditions. If a particular drill could not drill to design depth, they would likely change the bit or drill.

- While there will always be some uncertainty, engineers require more than a vague understanding of soil conditions to design the foundation of a building like this. Any remaining uncertainty should be taken into account in the design.

Re: Millennium Tower is tilting, sinking

#96

Post by vonmoltke »

omegaworks wrote: post #93
JosephHatfield wrote: post #61

Earlier quoted context omitted.

The city is currently requiring many owners of soft story buildings in the Outer Richmond district to pay for seismic refitting.

...And allowing them to pass on 100% of the cost to their renters.

So, you think landlords should operate at a loss for the benefit of their tenants?

Re: Millennium Tower is tilting, sinking

#97

Post by spikels »

honkhonkpants wrote: post #47
Animats wrote: post #19

From the article: "To cut costs, Millennium did not drill piles to bedrock." I'm amazed that a building of that height would be built on a slab with friction piles in the mudflat fill zone of the SF bay. How did they get a building permit for that? 16 inches of sinkage in 8 years is huge. Building sinkage isn't all that unusual, but not for skyscrapers. There was a time when skyscrapers were only built on competent r…

How did it get approved? The developer's lobbyist and PR rep is former mayor Brown's spokesman and personal friend, and at the time the current mayor was Newsom, a product of Brown's machine. Newsom was a bit of a crook in the area of real estate, having some self-dealing while he was on the board of supervisors and making sure all of his friends' problems got cleared. The same lobbyist also represents the Warriors i…

Nobody in SFgov is qualified to review the design of a skyscraper's foundation. That is why everyone involved in the project (city building inspectors, investors, lenders, etc) relie on expert engineering firms. Any firm making a mistake of this magnitude - if it is an engineering error - will be out of business and there insurers writing big checks.

While I agree Brown/Newsome/SFGov is shady but I highly doubt they are responsible for this problem. How did they fool the lenders? How did they get multiple engineering firms to sign off? Why would an investor like Millineum Partners want to take such a big risk in an area they have no advantage?

Re: Millennium Tower is tilting, sinking

#98

Post by overcast »

ChoGGi wrote: post #81
RGamma wrote: post #65

This brings me back to a question I have frequently asked myself: What do you do with unsafe or old skyscrapers? How would you raze such a thing? What if it falls over, breaks apart or breaks in on itself (9/11 gives an idea)? To a layman (with slight acrophobia) skyscrapers seem pretty fragile, and I'd much rather have them built into the ground than towards the sky, but obviously they're holding up in general and I…

Slowly? https://www.youtube.com/watch?v=jwf9LoS9Xt8

That's INSANE.

Re: Millennium Tower is tilting, sinking

#99

Post by jghn »

Finnucane wrote: post #31
Animats wrote: post #19

From the article: "To cut costs, Millennium did not drill piles to bedrock." I'm amazed that a building of that height would be built on a slab with friction piles in the mudflat fill zone of the SF bay. How did they get a building permit for that? 16 inches of sinkage in 8 years is huge. Building sinkage isn't all that unusual, but not for skyscrapers. There was a time when skyscrapers were only built on competent r…

Most of our big coastal cities are like that. Boston is about twice as big as it was in colonial times; all of the Back Bay is landfill. A lot of Cambridge is landfill. And yes, most of the taller buildings cluster around the more solid bedrock areas closer to downtown. But the engineering principles needed here aren't unknown--cities like Las Vegas and New Orleans have modern buildings that are much taller than were…

As a kid I always wondered why so many of the taller buildings clustered up near DTX and then down that little strip down Boylston. As I got a bit earlier and learned what Boston originally looked like, it all made sense.

Re: Millennium Tower is tilting, sinking

#100

Post by thebooktocome »

vonmoltke wrote: post #96
omegaworks wrote: post #93

Earlier quoted context omitted.

...And allowing them to pass on 100% of the cost to their renters.

So, you think landlords should operate at a loss for the benefit of their tenants?

On the other hand, how fast does an empty unit depreciate in value?
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