摘要
为探究地震波斜入射作用对坝后式厂房上部结构的影响,构建了龙开口水电站二维厂坝整体连接有限元模型,根据粘弹性边界理论,编制了平面P、SV波斜入射波动程序,输入地震波采用抗震设计要求的人工波,分析坝后式厂房上下游墙的动力响应可知,P、SV波斜入射作用下坝后式厂房上下游墙的动力响应与垂直入射时明显不同,从位移来看,SV波入射角度越大,上下游墙体的水平向位移峰值越大,高程越高,水平向位移峰值变化越快;从应力来看,随着SV波入射角度的增大,应力控制点的第一主应力逐渐减小,而P波斜入射时应力的变化规律与SV波相反。
A two-dimensional finite element model was established to explore the influence of obliquely seismic waves on the upper structure of power house at dam toe.The prototype of the model is Longkaikou hydropower house.The code of obliquely incident P-wave and SV-wave was built according to the viscoelastic boundary theory.Due to the seismic design requirements,the artificial waves were adopted as the input waves.The dynamic response of the upstream and downstream walls of power house at dam toe is significantly different from the normal incidence.With an increase in the incident angle of SV-wave,the peak value of horizontal displacements of the control points on the upstream and downstream walls gradually increase.The peak values of displacement change rapidly with the elevation increase.As for the first principle stress,the values of the stress control points decrease with the angle increase.On the contrary,the trend is opposite as the incident wave is P-wave.
引文
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