Seismic Damage Control of Long Span Cable-Stayed Bridges by Energy Dissipation Subsidiary Piers

China has been planning several sea-crossing projects consisting of long span bridges and tunnels. Long span bridge structures, which have low natural frequencies, may respond with large displacement after strong earthquake and suffer from damages on structural elements. The seismic performance of long span bridges is strongly dependent on structural systems. Therefore, it is significant to investigate the damage mechanisms of long span bridges and further, to propose novel structural systems with damage control concept for seismic design in order to satisfy the performance requirements.

In this paper, global response analyses will be carried out to investigate the seismic performance of a trial designed cable-stayed bridge (CSB) with a central span of 1400m excited by different ground motion intensities. The damage mechanisms and failure patterns will be discussed for various structural parameters. Based on the simulation results, structural systems with damage control strategies of sacrificing supporting piers will be presented and the required parameters for practice will be proposed to redesign the supporting piers.