【摘要】 列车提速加剧了车桥系统的耦合振动,为此结合天津轻轨工程分析了考虑土-结构相互作用(SSI)效应的车桥系统的耦合振动．分别建立了考虑SSI效应和不考虑SSI效应(即墩底固接)的车桥系统耦合振动的分析模型．在车桥系统模型中,建立了27个自由度的车辆模型;在桥梁模型中采用空间梁单元进行模拟;在考虑SSI效应中, 以弹簧和阻尼器模拟土介质的动力性质,将群桩基础等效简化为弹性地基梁．对天津轻轨工程一座四跨预应力混凝土连续刚构桥的数值仿真分析结果表明,考虑SSI效应,对桥梁结构的横向和扭转角位移响应影响显著,而对桥梁结构的竖向和纵向位移响应影响不大,其中横向位移最大增幅达90％,扭转角最大增幅接近38％．可见,处于地基软弱地区的铁路桥梁,SSI效应会对车桥系统的耦合振动产生不容忽视的影响．更多还原

【Abstract】 By referring to the construction of Tianjin Light Railway, the coupled vibration of the train-bridge systems is analyzed taking into account the influence of the soil-structure interaction (SSI) . The analytical models of the train-bridge systems including and excluding the SSI are established respectively. A model consisting of 27 degrees of freedom is set up for the train. The spatial beam element is adopted in the simulation for the bridge structure. Each pile-group foundation is equivalently simplified as one single beam by simulating the elastic soil around the foundation with springs and dampers. From the numerical simulation of a 4-span continuous framed bridge in Tianjin Light Railway, the results show that when SSI is considered, the lateral displacement and torsion angle responses are affected significantly, while the vertical and longitudinal displacement responses are only affected slightly. The maximal amplitude of the lateral displacement reaches 90% and the maximal amplitude of torsion angle is close to 38%. A conclusion can be given that the SSI effect on the coupled vibration of the train-bridge systems is significant for the railway bridges located in the soft soil areas.更多还原