Many new buildings in Seattle will fail. That's what the head of an earthquake consulting firm, Peter Yanev, concludes, after studying the damage from the February earthquake in Chile.
We engineers and seismologists need to gather and study as much data as we can from Chile's quake. But one thing is already clear: based on the kind of damage that buildings suffered in Chile, tall structures in the earthquake zones of the United States appear to be at much higher risk than we thought. This lesson should be of obvious concern to San Francisco and Los Angeles. But it is actually the Pacific Northwest that is most vulnerable to a mega-quake like Chile's.
. . .
Construction codes are based on the probability of earthquakes striking a region. That means Seattle's buildings, for example, are designed for roughly half of the earthquake loads of buildings in San Francisco or Los Angeles, because earthquakes occur roughly half as often in Seattle as in California's cities. But the result is that Pacific Northwest cities are full of buildings with slender structural frames and fewer and smaller shear walls. In a mega-quake, many of the region's iconic tall buildings would probably collapse. The loss of life and property from such a disaster would be far worse than the damage and death suffered in Chile.
Geologists believe — with good reason, as far as I can tell — that a mega-quake is inevitable in this area. Probably not soon, probably not even in my lifetime. But it will happen.
Cross posted at Jim Miller on Politics.
(More on the Cascadia fault here.)
Posted by Jim Miller at March 28, 2010 10:01 AM | Email ThisIf this report is true, I'd guess that upgrading the buildings downtown should be more of a priority than replacing the Viaduct. But I have a feeling that the massively expensive tunnel project is more of a way of punishing people for insisting on driving cars than anything else. The hostility of Seattle to automobiles and people living in the suburbs generally is the biggest reason I avoid spending my money there.
Posted by: jvon on March 28, 2010 11:49 AMThe solution is to legislate practical, cost effective things. But the big problem is we don't have any practical legislators or bureaucrats any more. They are so divorced from reality that whatever they do will be obsessive and expensive for little gain. Just like they always do.
Posted by: G Jiggy on March 28, 2010 11:55 AMUpgrading downtown buildings, against the Richter-9 quakes that hit Seattle every thousand years or so, has been in continuous progress at least since the early 80s. And of course the building permits that enable renovations require just that sort of upgrade as well. The only way the Viaduct escapes is that its owner, WSDOT, is not subject to the 'fix it or no occupancy permit' overlords of Seattle - and even the Viaduct has had periodic upgrades as well.
And I too have a feeling that the massively expensive tunnel project is more of a way of punishing people for insisting on driving cars than anything else. Just fix the viaduct to Richter-9 standards, and admit that its traffic is of tremendous civic and economic value to both its participants, and to those who receive goods and services directly from that traffic.
Posted by: Insufficiently Sensitive on March 28, 2010 03:26 PMI vote for commie joe, mike the park restroom boy scout, tensor, the Seattle Times editorial board, the headquarters for The Stranger, the Democrat Party of Washington State, Freeway Hall, Seattle Radical Women and NAMBLA to all relocate their collective sorry behinds into an unreinforced brick masonry building in Pioneer Square. At least if the "big one" hits, there will then be a silver lining.
Posted by: Attila on March 28, 2010 03:46 PMThe solution is to legislate practical, cost effective things.
Having lived in Chile, and lived through a few Earthquakes (but none of the magnitude that hit Concepcion), I can tell you the way to survive is to have very few tall buildings - to use short buildings, and spread them out.
Exactly the OPPOSITE of what the GMA forces on us. Our legislation and regulation drives the kind of development that will fail at much higher rates when the big one hits.
But the big problem is we don't have any practical legislators or bureaucrats any more.
Sad but true, sad but true...
Posted by: Shanghai Dan on March 28, 2010 05:48 PM