3 ms·

> The leaning building across from my office, for example, has nothing to do with seismic issues Nowhere in the article did anybody make such a claim. It was t

> The leaning building across from my office, for example, has nothing to do with seismic issues Nowhere in the article did anybody make such a claim. It was to illustrate the general problems of building in that area even without an earth quake, which leads me to the other point, what IMO is the main issue, and I think is pretty independent of how much effort is spent on any one building: The potential for soil liquefaction. They included several maps showing that many of the tallest buildings are built pretty much exactly over ground that might suffer that fate in a big earth quake. How would any individual design help? Compared to the alternative of not building the tallest structures right over those spots. The maps also showed plenty of more solid ground, but that is where there are mostly lower buildings. I would like to hear your opinion on that issue. As for your doubts on the entire article, it seems to me they asked quite a few specialists? Are they all mistaken? Well, I certainly would like you to be right, I used to live in SF and I still love the entire greater Bay Area.

abduhl 9y ago
Liquefaction mitigation is possible (ground replacement cells, compaction grouting, etc). It costs a lot and the only place that we (my company) have done true liquefaction mitigation is on large state funded jobs. The preferred alternative for the Bay Area is to sink foundations through liquefiable soils, discounting any strength from these soils, and rely on empirical studies that have found that liquefaction does not necessary result in loss of confinement which would induce buckling failures in the piles. I share the GP's doubts on the article. The practicing specialists they talked to certainly don't think there's a gamble: they actively pursue and design sky scrapers in the City. I think their words are being misused in a way that makes them seem like they agree with the article's premise.

abduhl 9y ago

Liquefaction mitigation is possible (ground replacement cells, compaction grouting, etc). It costs a lot and the only place that we (my company) have done true liquefaction mitigation is on large state funded jobs. The preferred alternative for the Bay Area is to sink foundations through liquefiable soils, discounting any strength from these soils, and rely on empirical studies that have found that liquefaction does not necessary result in loss of confinement which would induce buckling failures in the piles. I share the GP's doubts on the article. The practicing specialists they talked to certainly don't think there's a gamble: they actively pursue and design sky scrapers in the City. I think their words are being misused in a way that makes them seem like they agree with the article's premise.