Seismic Analysis and Retrofitting Priorities for Highway Bridges on EarthquakePriority Route System in Western Kentucky

摘要

Concern has grown in recent years over the seismic activity of the New Madridseismic zone in Western Kentucky. Bridges, as the vital links of the priority route system, need to be prevented from sever earthquake damages in order to keep the routes passible after an earthquake has occurred. In the report, seismic rating and seismic analysis were performed for each of 276 bridges on the priority route system. A priority order of retrofitting for the bridges was listed according to their vulnerability to the earthquake. At least 111 bridges need retrofitting based on the results of seismic analyses. The number of bridges needing to be retrofitted were determined for different confiodence levels. The methods of estimating span-loss type of bridge collapse due to earthquake induced abutment sliding and evaluating bridge damages related to earthquake induced vibration of pier or bent were developed. ATC analysis was also conducted for each bridge.