BART to install seismic sensors at 8 locationsBy Erik N. Nelson
The BART system is poised to install seismic sensors in eight locations, including the Transbay Tube, which the subway's spokesman says will help engineers determine whether trains can start running after an earthquake.
In a major quake, however, the sensors could serve as so-called black boxes to determine why subway structures failed, said the State Geological Survey geologist who supervises the seismic monitoring program.
By this summer, the tube will be fitted with five $1,000 sensors near each other at the bottom-hugging structure's San Francisco end, said Anthony Shakal, supervising geologist for the California Strong Motion Instrumentation Program. The program was started after scientists said they were frustrated by the lack of data near buildings and bridges that collapsed in the 1971 Sylmar earthquake in Los Angeles.
BART also will be installing clusters of sensors at the Ashby, Coliseum/Oakland Airport, MacArthur and Rockridge stations in Oakland, as well as the downtown Berkeley, Fremont and South San Francisco stations. The system already has sensors at the Hayward, Daly City and Orinda stations.
"Right now, when there's an earthquake, we stop all the trains and we go through the system" on foot to check for damage, said BART spokesman Linton Johnson.
"With this program, we will know within 20 minutes and within minutes once we fine-tune the system, what will be standing."
Copyright ©2006 The Argus. Published 04/08/2006.