高速铁路连续梁空心桥墩地震分析

Seismic Analysis of the Hollow Pier of High Speed Railway Continuous Beam

对于高速铁路常规跨度连续梁桥桥墩的地震力,目前设计者多采用抗震规范中单墩地震力计算公式计算,这与全桥模型的实际情况显然不符。为此,利用Midas/Civil软件建立了三种跨度连续梁的全桥空间动力模型,并通过改变基础的形式以及基础的边界条件来改变桥墩的整体刚度,分别将全桥模型计算的地震力结果与规范法的单墩模型计算的结果进行了比较,得出了两者比值(全桥模型数值/单墩模型数值)。当桥墩刚度越强时这个比值越小,桥墩刚度越弱时这个比值越大的结论。并给出了这个比值与刚度之间的关系曲线。最后提出了对于实体桥墩及考虑活动支座摩擦影响的展望。

For seismic force of the piers of continuous beam bridge of conventional span in the high speed railway,the designers usually calculate seismic force according to the single pier formula from the code for seismic design.Obviously it doesn’t conform to the real condition.Therefore,the paper makes use of Midas/Civil to build space dynamics models of three spans continuous beam bridge,which changes the pier stiffness by changing the foundation form and foundation boundary condition,compare respectively the seismic results of the whole bridge model with the results of the single pier model according to the code for seismic design,and draw the conclusion that the ratio（result of the whole bridge model/result of the single pier model） is more smaller when the pier stiffness is stronger,on the other hand,the ratio is larger when the pier stiffness is weaker,and give the relation curve between the ratio and pier stiffness,finally look into the future from the solid pier and the effect of the movable bearing friction.