Each building shakes differently during an earthquake. We study those differences to inform building codes and practices and potentially save lives.
How do we know what happens to buildings during earthquakes?
How buildings are affected depends on the size of the quake and how far the buildings are from the epicenter, what kind of soil they stand on, and what is beneath that soil. Shaking and damage also depend on the type and height of the structure, how it was constructed, and what has happened to it since then.
Until recently, seismic networks could not reveal an earthquake's effects on different soils, sites, and buildings in detail. Seismographs were too widely spaced to enable a high-resolution view of ground shaking, and seismic networks did not include buildings.
Now, researchers have placed inexpensive accelerometers, tiny devices that measure acceleration and are used in cell phones to detect motion and orientation, in buildings from the ground level to the top floor. The Community Seismic Network gathers data about how the ground and buildings move to inform safer construction and better damage detection.
In the video below, Caltech's Monica Kohler, a research professor of mechanical and civil engineering, describes the Community Seismic Network and how it gives new insights into shaking and building damage.