行波效应下铁路简支梁桥梁轨系统地震响应

基于多点激励的大质量法，采用非线性杆单元模拟梁轨接触，建立了考虑地震动行波效应的简支梁桥梁轨相互作用模型。以沪昆线上某5-32m简支梁桥为算例，分析了行波效应作用下轨道结构对桥梁地震响应的影响，研究了行波效应下钢轨和墩台的受力特性，并对相关参数的影响做了探讨。研究表明：行波效应下轨道结构将大大增强梁体和下部结构的地震响应；轨道对行波效应极为敏感，视波速越低轨道和墩台受力越大；支座布置形式和桥墩刚度突变对相邻桥墩受力影响显著；随着简支梁跨数的增加，钢轨和桥台受力逐渐增大并趋近于一定值。

Longitudinal interaction of simply-supported beams and CWR under traveling wave effect

Based on the large-mass method of multi-support excitation, the nonlinear bar element was used to simulate the beam-track contact. The track-bridge interaction model of simply-supported beams was established for the first time with considering the seismic traveling wave effect. Taking 5-32m simply-supported beams on the Shanghai-Kunming line as a case, the impact of track on the seismic performance of the bridge was analyzed under traveling wave effect. The force law of the track and pier was studied, and the influence of parameters was discussed. Studies have shown that the track greatly increases the seismic response of the beam and substructure under the traveling wave effect; the track is extremely sensitive to the traveling wave effect; the lower the surface wave velocity is, the larger the force exerted on the track and pier is; the bearing arrangement and the sudden change of the pier stiffness significantly affects the force of the adjacent piers; with the increase of the number of spans, the track and pier force gradually increases and approaches a fixed value.