大跨度双塔悬索桥在地震动行波激励下的响应规律研究

本文以一座主跨850m的大跨双塔悬索桥为工程背景,采用时程分析法研究了行波效应大跨双塔悬索桥地震响应的影响。通过建立三维有限元分析模型,在分析了大跨度双塔地锚式悬索桥动力特性及一致激励下地震响应规律的基础上,进一步探讨了行波效应对大跨双塔地锚式悬索桥地震响应的影响规律。分析结果表明:地震波纵向行波作用下,主塔的地震响应随着视波速的减小而先减小后增大;主梁的竖向振动则较一致激励下显著增大;主缆及吊索轴力则受地震动行波效应的影响不大。

Effect of Seismic Wave Passage Excitation on Seismic Response of Long-Span Suspension Bridge

Based on a realistic engineering project of a long-span suspension bridge,the seismic response under seismic wave passage is analyzed.After 3-D finite element model was established,dynamic characteristic and seismic response under uniform seismic excitation are analysed.Further,the affect law of wave passage excitation on seismic response of long-span suspension bridge is discussed.The results indicate that seismic response of tower decrease and then increase with the minishing of apparent wave velocity.However,seismic wave passage effect can amplify the seismic demand of girder and have little effect on the axial force of cables and slings.