摘要
地震动输入一直是工程抗震研究所关注的焦点。多跨连续梁桥纵向延伸较长,进行地震反应分析时应考虑有限波速所引起的行波效应。以某座12跨预应力混凝土连续梁桥为例,推导了结构的运动方程,采用有限元结构分析软件ANSYS建立了该桥的动力分析模型,进行了动力特性分析和时程分析。通过输入不同波速的地震波,计算行波激励下桥梁的地震反应,并和一致激励下的结果进行对比,分析行波效应对桥梁地震反应的影响。结果表明:随着波速的增大,桥梁的地震反应先减小后增大。
The earthquake input pattern is always a principal focus in the research on the earthquake resistance of engineering structures.The long-span continuous beam bridge has a large extended length longitudinally,the travelling wave effect should be considered in the analysis.Taking a 12-span P.C.continuous beam bridge as an example,the dynamic equation of the structure is derived,and the dynamic model of the bridge is also established by using the finite element analysis program ANSYS.Furthermore,the modal analysis and time history analysis of the bridge are carried out.Under the influence of the different earthquake waves,the results of the seismic response analysis of the bridge are numerically simulated and compared.It is shown that the seismic response of the bridge is first reduced,then indused with the increase of the velocity.
引文
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