中文摘要：

依据现行的《铁路工程抗震设计规范》，合理地选取大量强震记录作为地震动输入，采用单自由度弹塑性动力分析程序，对不同同有周期的弹塑性单自由度体系进行非线性动力时程响应分析，得到与我国现行《铁路工程抗震设计规范》相容的具有统计意义的弹埋性需求谱和强度折减系数谱，进而对简化能力谱法作了改进，并应用于某客运专线双柱式桥墩的抗震性能评估中，再将所求得的结构性能点转化为结构的非线性地震响应，并与80条强震记录非线性时程分析计算结果的平均值进行比较，从中可以看出：改进的简化能力谱法可以用较少的计算工作量得到比较精确的结构非线性地震响应。这也验证了将改进的简化能力谱法应用于我国铁路桥梁工程抗震性能评估的可行性。

英文摘要：

A large number of strong motion records are appropriately selected according to the current Code of Seismic Design for Railway Engineering. Nonlinear time history analyses for elasto-plastic SDOF with different natural periods are carried out, and the statistical elasto-plastic demand spectra and strength reduction factor spectra, compatible with the current Code of Seismic Design for Railway Engineering, are established. The simplified capacity spectrum method is improved and applied for one double-column bridge pier, and the nonlinear seismic response can be calculated. By comparing with the averaged result of nonlinear time history analyses, it can be concluded that the improved simplified capacity spectrum method can attain relatively accurate structural nonlinear seismic responses with less calculation work.