连续梁桥横桥向地震动分析

根据位于弹性基础上连续梁的变形特性，将桥墩的变形分解为自身弯曲变形、基础转动和平动引起的变形三个部分，上部结构的横桥向变形采用三阶Hermit多项式插值，并将上下部结构变形作为各自的振型函数。由拉格朗日方程建立全桥的地震振动方程，从而得到包含地基特性综合参数的结构自振频率以及振型参与系数。利用锤击法进行了模型试验，结果表明计算方法可行，可供连续梁桥抗震设计及抗震评估时参考。

Transverse Seismic Analysis of Continuous Bridges

The piers' deformations on the elastic foundation include the elastic deformation caused by load and the deformations derived from the foundation's rotation and translation. The modal shape function of the piers is put forward, and that of superstructure is assumed by means of Hermite polynomial, then the whole seismic vibration equation of continuous beam is given on the basis of the Lagrange Equation, thus the structure's frequency and the influencing coefficient of their vibration modes can be calculated, which involve the foundation's complex parameters. Modal experiment using impact excitation method has testifed the validity of the presented method. It can give reference to the seismic design and assessment of continuous bridges.