DISPLACEMENT-BASED SEISMIC SAFETY ASSESSMENT OF EXISTING MUNICIPAL BRIDGES

The basic procedure and method of the displacement-based seismic safety assessment of existing municipal bridges are introduced. Displacement ductility coefficient of pier, reinforcement tension strain and concrete compression strain at the bottom section of pier are adopted as assessment parameters. Based on the world-wide accepted structural seismic design philosophies and by comparing earthquake resistant capacity and earthquake demand of structures, principles of seismic safety assessment of existing municipal bridges are proposed. Using the displacement-based method and the assessment principles, seismic safety assessments of 5 Beijing existing municipal bridges were performed. The assessment results can serve as the bases for strengthen decision making of these bridges.