中文摘要：

针对新郑大桥改建后提速列车通过时，墩顶横向振幅超过《铁路桥梁检定规范》规定的通常值，建立列车一桥梁系统振动计算模型，运用列车脱轨能量随机分析理论，对该桥上列车走行安全性进行计算分析；在列车不脱轨的条件下，对桥上列车正常运行的平稳性进行研究；对墩顶横向振幅超《铁路桥梁检定规范》规定的通常值与行车安全的关系进行分析。研究结果表明：在车速不超过80km／h时，列车可以安全运行，平稳性也基本满足要求；将墩顶横向振幅通常值当成行车安全限值是不合理的。

英文摘要：

The lateral amplitude of pier exceeds ordinary value given by code for rating existing railway bridges, when speed-raised train passes through the new Xinzhen Bridge. Whether the lateral rigidity of the bridge satisfies the requirement of running train needs to be answered. The computing model for train-bridge system vibration was presented, and the safety of running train on the bridge was analyzed with energy random analysis theory for derailment. On condition that train will not derail, the smoothness of running train on the bridge is analyzed. The results show that train can pass through the bridge safely within the speed of 80 km/h and the smoothness of train satisfies corresponding code. The relationship between ordinary value of pier and safety of running train is discussed, and it is unreasonable to regard the ordinary value of pier as the limit value of traffic safety.