中文摘要：

为研究多维地震作用下桥梁-无砟轨道非线性相互作用规律,以沪昆高铁16×32 m简支箱梁桥为例,建立了充分考虑无砟轨道结构层间纵横竖向非线性约束的桥上CRTSⅡ型板式无砟轨道系统仿真模型,并与桥上CRTSⅠ型双块式无砟轨道系统对比,探讨其地震响应特征,研究水平地震激励角对系统受力、变形的影响,及多维地震耦合作用下桥梁-无砟轨道系统地震响应规律.与桥上CRTSⅠ型无砟轨道系统相比,桥上CRTSⅡ型无砟轨道系统地震响应特点主要表现为：底座板与桥面板之间通过摩擦系数极小的滑动层滞回耗能,大幅提高系统抗震性能;钢轨应力包络曲线较为平滑且数值相对较小;挡块对轨道竖向变形起到一定约束作用,地震中底座板和挡块之间存在频繁的碰撞现象;轨道结构竖向约束相对较弱,地震时钢轨将出现较大幅度的竖向位移.此外,水平地震激励角对桥上无砟轨道系统受力和纵横向变形影响显著,在进行地震响应分析时必须考虑地震激励角的影响;在进行地震作用下轨道结构变形分析时,应考虑多维地震耦合作用的影响.

英文摘要：

Taking a 16×32 m simply supported box girder bridge of Shanghai-Kunming high-speed railway as an example,a simulation model for CRTSⅡ slab ballastless track system on bridge which fully considered lon-gitudinal,transverse and vertical nonlinear constraints among ballastless track structure layers was estab-lished,so as to study the nonlinear interaction between ballastless track and bridge under multi-dimensional earthquake.After a comparison was made with CRTSⅠ double block ballastless track system,its seismic re-sponse characteristics,the effect of different angles of horizontal seismic excitation on the stress and deforma-tion of the system as well as seismic response laws of bridge-ballastless track under the coupling effect of multi-dimensional earthquake were studied.Compared with CRTSⅠ ballastless track system,the seismic perform-ance of the CRTSⅡ ballastless track system on the bridge was significantly improved because of the hysteretic energy dissipation between base plate and deck due to the tiny friction coefficient of sliding layer.The envelope curve of rail stress was relatively smooth with relatively small numerical value.Stoppers played a role in re-straining the vertical deformation of the track.Frequent collisions occurred between stoppers and base plate un-der seismic action.Besides,a relatively considerable vertical displacement may appear in rails with relatively weak vertical constraint of the track structure.The influence of horizontal earthquake excitation angle must be＆amp;nbsp;considered during the analysis of seismic response,given significant influence of horizontal earthquake excita-tion angle on the force as well as longitudinal and transverse deformation of ballastless track system on bridge. The coupling effect of multi-dimensional earthquake should also be considered during the analysis of the track structure deformation under seismic action.