Abstract:In order to find out the appropriate longitudinal seismic constraint system for multispan cable stayed bridge,an analysis is made of the dynamic characteristics and linear seismic response of the bridge under four kinds of rigid constraint systems between girder and different pylons in longitudinal direction based on a cable stayed bridge with six pylons in China.The results indicate that,for a multispan cable stayed bridge,only changing the positions of rigid constraints,the partial pylons constraint system is not appropriate for seismic performance; the system with all the pylons being constrained by girder or the total floating system can diminish the difference of seismic response of different pylons,but when multispan cable stayed bridges with total floating system are used in soft soil condition,special attention must be paid to the seismic design of side pylon and structural longitudinal displacement.
