Structural system studies on super long-span cable-stayed bridge under earthquake

Several sea-crossing projects consisted of long span bridges and tunnels are under planning in china. And the aseismic performance of long span bridges is dependently on the structural system when suffering from strong earthquake. So, it is importance to analyze the seismic performance of several structural systems for cable-stayed bridges. Firstly, according to acceleration and displacement response spectrum, aseismic concept analysis is carried out for structural systems of cable stayed bridge. And seismic performance index is determined to evaluate the response of long-span cable-stayed bridges which is the displacement and internal force. In this paper, aiming at a trial cable-stayed bridge with a center span of 1400 m, the numeral simulation techniques are utilized to analyze and compare several structural systems performance of cable-stayed under strong earthquake. The results show that the structural system installed elastic restriction or damper will improve the seismic performance which may give consideration to both the performance indexes. The structural system will be reasonable to seismic design of long-span cable-stayed bridge.