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> If your theory is that the building code is just fine when things like the Millennium Tower can happen, then we disagree on what "fine" means. What portion o

by ggcdn 9y ago

> If your theory is that the building code is just fine when things like the Millennium Tower can happen, then we disagree on what "fine" means. What portion of the building code do you think needs to be updated in response to the Millennium situation? In reality, the building code achieves a success rate far in excess of what engineers deem acceptable. It is unfortunate that the Millennium is a big glaring exception, but the fact remains. Geotechnical engineering (the cause of the Millennium lean) remains a highly empirical field of engineering with uncertainties that dwarf structural ones. Hence there is a lot of built-in conservatism in design parameters like bearing pressures. But there are limits to the amount of information you can ascertain of what's below you that you cannot see. Looking back in retrospect and saying "well obviously they should have had longer piles" like many people have on the various threads about the tower is a pretty ignorant thing to say, and it shows that they do not have an appreciation of the engineering behind the decision. There a tens of thousands of examples of friction piles that have worked flawlessly. The engineering evidence appears to have supported the decision, but the in-situ soil conditions varied from their design model. This, in my opinion, is not a failure of codes, but an unfortunate, statistically rare outcome.

wpietri 9y ago
Engineers may deem this acceptable, but given that San Francisco taxpayers may end up footing the bill, I doubt the rest of us do. I understand that the people who built it believed that they were doing just fine. But I also understand that there are enormous pressures to keep costs low on a project like this. The notion that for this building those enormous pressures had exactly zero contribution to this outcome is a claim I certainly wouldn't accept without evidence. If this were really in the range of statistically expected outcomes, then a) there should have been a plan in place to fix it before the structure went up, and b) they would have had sufficient insurance coverage to pay for the fix. Neither is true. The ongoing gosh-golly-who-cooda-node routine plus the simultaneous festival of blame-shifting suggests to me that, at best, the business side of the operation went well beyond what an engineer would have done in the same place. The correct fix to the building code here I'm happy to leave to the experts, just as long as they eliminate outcomes like this. If that ends up raising the costs for other fancy buildings stuffed with pied-a-terres for the wealthy even to prohibitive levels, I am entirely fine with that. Erring on the side of of earthquake safety while building near major faults in major metropolitan areas seems like a great choice to me.
- ggcdn 9y ago
  > just as long as they eliminate outcomes like this I guess the point I'm trying to make is that complete elimination isn't possible in a long tail statistical distribution. There will always be a point where we have to draw the line, and there will always be freak occurrences of undesirable outcomes. This is the crux of engineering - finding the correct balance between cost and safety. Perhaps the current state is not enough, but the wildly disproportionate amount of structures that are working just fine tells me we are close. > If that ends up raising the costs for other fancy buildings stuffed with pied-a-terres for the wealthy even to prohibitive levels, I am entirely fine with that. Building codes aren't only applied to high end buildings. Any changes affect the (badly needed) low end housing just as much as high end buildings. Just another thing to consider. > Erring on the side of of earthquake safety while building near major faults in major metropolitan areas seems like a great choice to me. No disagreement there ;)
  - wpietri 9y ago
    The outcome I'm referring to isn't just the sinking building. It's the clusterfuck of a sinking building and years of chaos that could spill over into extensive costs for others. Long-tail outcomes perhaps can't be eliminated, but they can be 100% mitigated through planning and insurance. Medical care has a much longer tail, for example, but many countries manage to provide full financial coverage and individual support in treating and managing even very rare diseases. If you're saying this was a reasonably forseeable but unlikely outcome of cost-driven skipping out on the bedrock anchoring that neighboring buildings used, the I don't think it's too much to ask them to have an answer to the question of, "Ok, if your cheap solution doesn't work, what will you do next?" And if they don't have a good answer to that, I also don't think it's too much for them to not be allowed to build the thing.

by ggcdn 9y ago

wpietri 9y ago

Engineers may deem this acceptable, but given that San Francisco taxpayers may end up footing the bill, I doubt the rest of us do. I understand that the people who built it believed that they were doing just fine. But I also understand that there are enormous pressures to keep costs low on a project like this. The notion that for this building those enormous pressures had exactly zero contribution to this outcome is a claim I certainly wouldn't accept without evidence. If this were really in the range of statistically expected outcomes, then a) there should have been a plan in place to fix it before the structure went up, and b) they would have had sufficient insurance coverage to pay for the fix. Neither is true. The ongoing gosh-golly-who-cooda-node routine plus the simultaneous festival of blame-shifting suggests to me that, at best, the business side of the operation went well beyond what an engineer would have done in the same place. The correct fix to the building code here I'm happy to leave to the experts, just as long as they eliminate outcomes like this. If that ends up raising the costs for other fancy buildings stuffed with pied-a-terres for the wealthy even to prohibitive levels, I am entirely fine with that. Erring on the side of of earthquake safety while building near major faults in major metropolitan areas seems like a great choice to me.

ggcdn 9y ago
> just as long as they eliminate outcomes like this I guess the point I'm trying to make is that complete elimination isn't possible in a long tail statistical distribution. There will always be a point where we have to draw the line, and there will always be freak occurrences of undesirable outcomes. This is the crux of engineering - finding the correct balance between cost and safety. Perhaps the current state is not enough, but the wildly disproportionate amount of structures that are working just fine tells me we are close. > If that ends up raising the costs for other fancy buildings stuffed with pied-a-terres for the wealthy even to prohibitive levels, I am entirely fine with that. Building codes aren't only applied to high end buildings. Any changes affect the (badly needed) low end housing just as much as high end buildings. Just another thing to consider. > Erring on the side of of earthquake safety while building near major faults in major metropolitan areas seems like a great choice to me. No disagreement there ;)
- wpietri 9y ago
  The outcome I'm referring to isn't just the sinking building. It's the clusterfuck of a sinking building and years of chaos that could spill over into extensive costs for others. Long-tail outcomes perhaps can't be eliminated, but they can be 100% mitigated through planning and insurance. Medical care has a much longer tail, for example, but many countries manage to provide full financial coverage and individual support in treating and managing even very rare diseases. If you're saying this was a reasonably forseeable but unlikely outcome of cost-driven skipping out on the bedrock anchoring that neighboring buildings used, the I don't think it's too much to ask them to have an answer to the question of, "Ok, if your cheap solution doesn't work, what will you do next?" And if they don't have a good answer to that, I also don't think it's too much for them to not be allowed to build the thing.