中文摘要：

对车辆桥头跳车问题，提出一种分布式弹簧-阻尼单元，该单元可以考虑车轮一路（桥）面接触长度和车轮的动力特性。基于此单元，结合车辆有限元动力分析，可对车辆上、下桥头错台时的竖向动力荷载进行定量研究。实例分析表明：①分布式弹簧一阻尼单元由于考虑了桥头跳车时车轮与桥面的接触长度，所得的车轮竖向动荷载比以往方法有所降低；②桥头错台跳车造成的竖向轮载冲击系数可能超过我国和美国桥梁规范设计值，需要引起重视；③下桥跳车时车轮动荷载降低，可能造成车轮脱空，影响行车安全性；④跳车动力荷载与行车速度、错台高度等因素有关，相关参数分析有利于对桥头错台高度和行车速度进行合理控制。

英文摘要：

For study of vehicle bumping at bridge-head, a distributed spring-damper element is presented, in which the contact length between the tire and the road, and the dynamic characteristics of the tire are considered. Based on this element, the vehicle is modeled using the finite element method. The vertical dynamic load of the vehicle when it passes through the staggered platform at bridge- head is analyzed. Numerical examples show that： （~） The vertical dynamic load of the vehicle calculated using the distributed spring-damper element is less than that from the previous method because the contact length between the tire and the road is considered; （2） The impact factor of the dynamic load in vehicle humping at bridge-head may be higher than the value provided by the Chinese and American design codes of bridge, and it should be paid attention to; （3） Because the dynamic load of the vehicle decreases significantly when it gets off the staggered platform of a bridge, the tire is likely to dynamic load is affected by the speed of the vehicle are beneficial to the control of the dynamic load. detach from the road, and that is dangerous for driving; and height of the staggered platform, thus analyses of these （4） The factorsdynamic load is affected by the speed of the vehicle and height of the staggered platform, thus analyses of these factors are beneficial to the control of the dynamic load.