竖向地震对大跨度连续刚构铁路桥地震响应的影响

以内蒙古在建的大准铁路增二线黄河连续刚构特大桥为研究对象,采用反应谱分析方法研究了其在水平地震单独作用下、《公路桥梁抗震设计细则》和《铁路工程抗震设计规范》中规定的不同竖向地震分别同水平地震组合下的地震响应。结果表明:考虑竖向地震对连续刚构桥的地震响应非常明显;水平地震和《铁路桥梁抗震规范》中的竖向地震组合时结构地震响应较按《公路桥梁抗震设计细则》竖向地震组合时结构地震响应大,内力最大增幅为27%,位移为26%。

Effects of the Vertical Earthquake on the Seismic Response of Long-Span Continuous Rigid-Frame Railway Bridges

With the Yellow River continuous rigid-frame bridge under construction of the Da-Zhun Second-line Railway in Inner Mongolia as the subject of our research,the seismic response of the continuous rigid-frame bridge and the effects of the single excitation of horizontal earthquake and combined excitation of horizontal earthquake and vertical earthquake are analyzed and studied by means of the response spectrum prescribed in 《Detailed Rules for the Anti-earthquake Design of Highway Bridges》and 《The Anti-earthquake Design Norm for Railway Projects》.The result shows that the effect of the vertical earthquake on the seismic response of the bridge is very obvious and the seismic response with the combined excitation of the horizontal earthquake and vertical earthquake prescribed in 《The Anti-earthquake Design Norm for Railway Projects》is greater than that with the horizontal earthquake prescribed in 《Detailed Rules for the Anti-earthquake Design of Highway Bridges》,with the internal forces maximally increasing 27%,and the displacement increasing 26%.