Abstract:Taking a long-span double-pylon spatial cable plane self-anchored suspension bridge as the background, the applicability of typical seismic isolation and energy dissipation devices to bridge seismic isolation and energy dissipation under different seismic fortification intensities is systematically expounded. At the same time, based on the finite element numerical simulation method, 7 finite element models with distinct constraint systems are constructed to carry out the modal analysis and seismic response spectrum analysis in order to reveal the influence of various constraint systems on the structural dynamic characteristics and seismic responses. The research results show that for a double-pylon spatial cable plane self-anchored suspension bridge, it is a reasonable seismic restraint system to adopt elastic constraints between pylon and girder, and fully release constraints between piers and girder in the longitudinal direction of the bridge, and complete constraints between pylon and girder, and have elastic constraints between piers and girder in the transverse direction of the bridge. Whether vertical supports are set up for pylons and girder has little impact on the seismic response of bridges. The proposed “longitudinal - transverse - vertical” rational seismic constraint system can provide some references for seismic design of similar bridges.
