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Best Place to Ride Out "Big One" May Be Closer Than You Thought

Be It Ever So Humble, There's No Place Like Home

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    NEWSLETTERS

    In an earthquake, one of the best places to be is a wood-framed building. Not every building is built of wood, however, and there are other locations that can withstand the shaking ground. Patrick Healy reports from downtown LA for the NBC4 News at 6 p.m. on Monday, March 17, 2014.

    When it comes to earthquakes, there may indeed be no place like home.

    "I think our best buildings are our wooden houses," said Tom Heaton, a CalTech professor and director of the Quake Engineering Research Lab. "They've been through very severe shaking, and almost no history of collapse."

    The helpful attributes are their low height, light weight, the resilience of wood, and the aptitude of plywood sheets for serving as shear walls to prevent buckling, according to Heaton.

    Understanding Quakes: Faults Below Surface

    [LA] Understanding Earthquakes: The Faults Below The Surface
    Seismologists say the earthquake that shook Los Angeles early Monday morning was caused by an erupting fault about five miles below the Santa Monica mountains. Caltech is studying the many faults that run under California's ground. Conan Nolan reports from Pasadena for the NBC4 News at 5 p.m. on Monday, March, 17, 2014.

    Such a home might be your best location to ride out the inevitable "Big One," provided you've secured water heaters, big screen televisons, book cases, picture frames, and other objects that could become missiles.

    Unfortunately, wood framing does not scale up well, and larger and taller buildings require heavier
    materials and more sophisticated designs, which in some cases have proven to have unanticipated vulnerabilities.

    Quakes showed the need for reinforcement in buildings made of brick, "non-ductile" concrete, and with so-called soft stories that lack adequate bracing against pancaking.

    It was not until the 1960s that Los Angeles even permitted buildings taller than the 19-story City Hall.

    Seismic strength is a specific consideration in the design of steel-framed skycrapers, but even then, there can be surprises.

    After the Northridge quake, welds were found to have cracked in the frames of several buildings designed to withstand much stronger quakes.

    When it came time for Los Angeles to build a new emergency operations center, one requirement was a building that could survive the anticipated "Big One" earthquake and continue to function as coordination headquarters for the response.

    The city chose a design of "base isolation," which uses flexible connections between the
    building and its foundation, enabling the ground to move beneath the building.

    "The building will shake; the ground around it will shake much more, and the structure will remain intact," said Anna Burton, asst. general manager of the Los Angeles Department of Emergency Management.

    "It is one of the safest buildings in California, if not the entire US," said Mitchell Englander, chairman of the City Council's Public Safety Committee.

    Base isolation buildings are good at minimizing the damage suffered in moderate quakes, said Heaton. But there is a limit to how much ground motion they can withstand before the isolation units reach the end of their range of motion.

    The Los Angeles Emergency Operations Building was designed for a magnitude 8.0 quake.

    The Emergency Center opened in 2008 and has been activated dozens of times, but not yet for a major quake,  and so has yet to undergo its first real-world test.

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