大跨钢桁架拱桥地震响应有限元分析

采用ANSYS建立某大跨钢桁架拱桥有限元模型,对其进行模态分析;采用瑞利阻尼理论,通过拱桥前2阶圆频率计算质量阻尼和刚度阻尼;采用动力时程分析法对拱桥进行地震响应有限元分析.结果表明:横向位移的最大峰值由水平地震波载荷沿横桥向输入决定,纵向位移的最大峰值由水平地震波载荷沿纵桥向输入决定,竖向位移的最大峰值由重力载荷工况决定.

Finite element analysis on seismic response of large-span steel truss arch bridge

The finite element model of a large span steel truss arch bridge is built by ANSYS. The modal analysis is performed on the model. Using Rayleigh damping theory, the mass damping and stiffness damping is built by the first two order circular frequencies. The dynamics time history analysis method is used to do the finite element analysis on the seismic responses of the arch bridge. The results show that, the maximum peak value of displacement in the transverse direction is determined by the horizontal seismic wave load which is input along the transverse direction of the bridge, the maximum peak value of displacement in the longitudinal direction is determined by the horizontal seismic wave load which is input in the longitudinal direction of the bridge; the maximum peak value of displacement in the vertical direction of the bridge is determined by the gravity load.