Rapid Seismic Loss Evaluation System of Exiting Bridges in Taiwan

摘要

Located at the western Circum Pacific Seismic Belt, Taiwan suffers from earthquakes frequently. Therefore, the establishment of a rapid seismic risk evaluation system could help in reducing seismic disaster of the bridges. Based on the recorded earthquakes with magnitude over 5.0 during 1990 to 2003, this paper performed the regression analyses of attenuation law of peak ground acceleration (PGA) for the stations, all over Taiwan, set up by the Central Weather Bureau (CWB) under the Taiwan Strong Motion Instrumentation Program. The comparisons between simulated seismic intensity and actual one for some recent earthquakes were made sequentially to assure the precision of analysis. Based on the result, this paper determined the deteriorated plastic hinge properties of the neutralized RC bridge column and performed the pushover analysis to obtain the decayed seismic capacity curves. As a result, the time-dependent fragility curves with respect to some representative damage levels can be established and the possible seismic loss can be expressed as a function of service time.