中文摘要：

以日本某大跨度钢桁架桥梁为算例，采用TDAPⅢ非线性结构动力分析软件进行地震作用下的非线性动力特性分析，通过时程分析法研究了桥梁各构件内力和变形的最大地震响应值．根据分析结果，指出此桥现有的抗震能力不能满足桥梁抗震规范的要求，需要进行加固处理．

英文摘要：

Taking a Japanese long-span steel truss bridge as an example, this paper analyses its nonlinear dynamic response under the seismic force by using the nonlinear structural dynamic analysis software called TDAP Ⅲ and investigates the largest values of internal forces and deformations by means of the time-history analysis method. The results show that the current antiseismic capacity of this bridge can not satisfy the antiseismic code requirements and reinforcement is necessary.