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Structural engineer Patrick Buscovich grabs an oversize metal ruler and stands it upright atop the table like Christopher Columbus planting a flag on the shore of the New World. Then, unlike Columbus, Buscovich triggers an earthquake.
He shakes his hand back and forth, unleashing waves up and down the vertical ruler; its jiggling midsection quickly appears to be in three places at once. Meanwhile, the top of the ruler sways back and forth, slowly and methodically, like a metronome atop a piano.
That, Buscovich says, is what will happen to a high-rise condominium when an earthquake hits. And it will happen: Both high-rises and major quakes are inevitable parts of San Francisco's future.
"We have never seen really tall buildings go through [a major] earthquake," he says. "I'd like to see one or two big buildings go through one so we can say, 'Boy, we've really got this figured out.' I really wish we were phasing into this."
That won't happen. On the contrary, San Francisco is going all-out. The massive skeletons of partially constructed high-rise condos have become a ubiquitous feature of the city, and many more skyscraper condos are in the works. By now, the imminent transformation of San Francisco's skyline is an accepted notion for any curious city dweller. Less well-known, however, is that the city's tallest downtown skyscrapers are not built to a higher survivability standard than a bungalow in the Sunset.
At the heart of the thousands of pages of codes and regulations governing construction is the fact that all buildings are engineered to meet a remarkably straightforward standard: A structure of two, 10, or 70 stories should "not experience collapse" in the largest conceivable quake.
At the end of a massive temblor, "If everyone can walk away from the building safely and the building is completely trashed, that's fine," says Ephraim Hirsch, a veteran structural engineer and former president of the Building Inspection Commission. "That's a successful design,"
But is that good enough? While all buildings are held to an equal standard, not all buildings are equal. As Buscovich notes, a mortally wounded two-story building is a nuisance mostly to itself, but "a 50-story building is so big it predominates an entire neighborhood. ... Do we want a higher standard for that building if it has a problem and affects two whole city blocks?"
Engineers with UC Berkeley's Tall Building Initiative released a study earlier this year finding that high-rises are inherently more dangerous than shorter structures in two areas. Windows shattering in a tall building will shower a larger radius than those falling from a shorter structure. Also, in an emergency, most high-rise inhabitants must travel a long way to reach an exit.
And yet these problems won't be thoroughly analyzed prior to San Francisco's entering a high-rise building bonanza. Influential developers have chilled the discussion of whether San Francisco should improve its standards by threatening to take their building projects elsewhere if the city were to do so.
Almost universally, the high-rises sprouting in San Francisco use complex computer modeling techniques to justify building practices that would be forbidden by the city's traditional building codes. With the longstanding codes regularly overlooked, UC Berkeley researchers formed the aforementioned Tall Building Initiative to develop new "design criteria that will ensure safe and usable buildings following future earthquakes."
One of the initiative's foremost tasks was to determine how the state's builders felt about constructing high-rises to do more than merely survive the next big quake. And when its investigators queried local developers about their position on higher performance standards for tall buildings, the response was blunt and unambiguous.
The developers — whom the Tall Building Initiative declined to identify — said if San Francisco adopted exclusive building codes for high-rises, they'd be inclined to relocate their projects to less discerning cities.
Calls to multiple developers about their position were not returned by press time. The Residential Builders Association of San Francisco also didn't call back.
But the developers' threats weren't the only obstacle thrown Moehle's way. Shortly after Isam Hasenin took over the San Francisco Department of Building Inspection in mid-March, he abruptly pulled the city out of its working partnership with the Tall Building Initiative. Calls to Hasenin were returned by communications manager Bill Strong, who said Hasenin's decision to cut ties was strictly financial — so Moehle's group won't be getting the $250,000 toward its operating budget it was counting on.
Strong confirmed what others in city government and the building community had said off the record: Hasenin is an avowed opponent of cities adopting building codes more stringent than the state's, so he was fundamentally opposed to the Tall Building Initiative's research into higher performance standards from the outset.
In fact, the San Francisco Planning and Urban Research Association (SPUR), a city think tank, is also preparing a paper on seismic standards. Executive director Gabriel Metcalf acknowledged Hasenin has already advocated against more stringent building standards with him.