研究目的：为研究重载列车编组与运行对双线桥梁动力响应的影响,以朔黄重载铁路线上一座32 m预应力混凝土双线简支T梁为研究对象,建立重载列车-轨道-桥梁耦合有限元模型,并通过现场试验验证有限元模型的准确性,研究重载列车通过双线桥梁时的动力响应,分析重载列车不同编组方式、重载列车双线对开运行等因素对双线桥梁动力响应的影响规律。
研究结论：（1）动力响应计算结果与实测值吻合较好,表明所建立的重载列车-轨道-桥梁耦合有限元模型的可靠性高;（2）重车编组对桥梁的位移响应和动应变影响最大,对加速度的影响最小;空车编组对桥梁的加速度响应最大;空重混编次之,其中重车在前空车在后的混合编组对空车的位移响应影响较大,可能引起空车脱轨;（3）重车空车双线对开运行下桥梁的动力响应随着车速的提高而增加,与重车单线运行下桥梁的动力响应规律相似;在相同车速下,双线对开运行下桥梁的跨中竖向动力响应峰值均比重车单线运行下略大,而横向动力响应峰值比重车单线运行下小;（4）当重车与空车入桥距离差值为车体长度的整数倍时,桥梁的动力响应峰值与重车空车同时上桥时基本相等;当入桥距离差值为车体长度一半的整数倍时,桥梁的动力响应峰值有所降低;（5）本研究成果可为新建重载铁路双线桥梁的设计提供参考。

Research purposes: In order to study the influence of marshalling and operation of heavy haul train on dynamic response of double-track bridge, selecting a 32 m prestressed concrete double-track simply-supported T-beam on the Shuozhou-Huanghua railway line as the research object, the coupling finite element model of heavy haul train-track-bridge was established, and the accuracy of the finite element model was verified through field tests. The dynamic response of heavy haul trains passing through double-track bridges was studied, and the influence of different marshalling modes and single-track and double-track operation of heavy haul trains on the dynamic response of double-track bridges were analyzed.
Research conclusions:（1）The calculated results are in good agreement with the measured values, indicating the high reliability of the coupled finite element model of heavy haul train-track-bridge. （2）The loaded train marshalling has the greatest impact on the displacement response and dynamic strain of the bridge, and the smallest impact on the acceleration.The acceleration response of empty train marshalling to the bridge is the largest. The mixed marshalling of empty and loaded train takes the second place, and the mixed marshalling of empty vehicles in front of empty vehicles in the rear has a greater impact on the displacement response of empty vehicles, which may cause the derailment of empty vehicles.（3）The dynamic response of the bridge under double-track operation of loaded and empty vehicles increases with the increase of vehicle speed, which is similar to the loaded vehicles. The peak value of vertical dynamic response of the bridge under the double-track split operation is slightly larger than that under the single-track operation, while the peak value of transverse dynamic response of the bridge is smaller than that the single-track operation. （4）When the distance difference between the loaded vehicle and the empty entering the bridge is an integral multiple of the length of the vehicle body, the peak dynamic response of the bridge is basically the same as that when the loaded vehicle and the empty vehicle enter the bridge at the same time. When the distance difference into the bridge is an integral multiple of half the length of the vehicle body, the peak dynamic response of the bridge decreases.（5）The research results can have a reference for the design of new heavy haul railway double-track bridge.