以上海局管内某线由板式橡胶支座支承的16m预应力混凝土梁体的3座桥梁为研究对象,对其动力特性分析得出其横向一阶振型是以橡胶支座做横向剪切的平面摆动,并由实测固有频率推算支座的剪切刚度,进而粗略计算梁体在机车DF4及货车作用下的有载自振频率,与机车DF4及货车某一速度下的蛇形频率进行比较,进而得出在机车DF4和货车作用下结构出现横向振幅过大的原因。 Based on the analysis of the dynamic characteristics of three bridges of a 16m prestressed concrete beam supported by a slab rubber bearing at a certain line in the tube of Shanghai Administration, the transverse first-order mode of vibration is transversely sheared by a rubber bearing And the shear stiffness of the support is deduced from the measured natural frequency, and then the natural frequency of the load under the action of the locomotive DF4 and the truck is roughly calculated and compared with that of the locomotive DF4 and the freight car at a certain speed , And then come to the locomotive DF4 and trucks under the action of the structure appears horizontal amplitude is too large reason.