Anti-seismic performance analysis of cable-stayed bridge with different bearing constraint system

In order to find out the appropriate seismic constraint system for single pylons and double cable planes cable-stayed bridge,the space finite element model of the bridge with different constraint system was established by using the software Sap program:tower is free in longitudinal direction and transition piers is free in longitudinal and lateral directions;tower is constrained in longitudinal and lateral directions and transition piers is constrained in lateral direction.The two kinds of constraint system are regarded as Scheme 1 and Scheme 2.The analysis of the structural natural vibration characteristic and response under earthquake wave were carried out.The results of calculation indicate that,comparing with Scheme 1,the shear at the tower bearing,the force of tower,the displacement at transition piers and tower bearing of scheme 2 are all reduced,and the safety of tower of scheme 2 is enhanced.So Scheme 2 is adopted in the paper.