考虑车轮-路面接触长度的桥头跳车动力荷载分析  

Numerical analysis of dynamic load in bridge-head bumping considering the contact length between tire and road

作　　者：丁勇[1] 诸葛萍[1] 谢旭[2] 李辉[1] 黄剑源[1] 

机构地区：[1]宁波大学土木工程系,宁波315211 [2]浙江大学土木工程系,杭州310027

出　　处：《振动与冲击》2013年第9期28-34,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(50778160);浙江省自然科学基金(Y1110548);宁波市自然科学基金(2009A610157)

摘　　要：对车辆经过桥头错台时的动力荷载进行分析,提出考虑轮胎-路面接触长度的车轮模型,并计及车轮的滚动轨迹。结合有限元动力学分析方法,对车辆上、下桥头错台时的动力荷载进行定量分析。数值仿真表明:考虑接触长度的模型更符合车轮与路面接触的实际情况,动力荷载计算值较平缓;下桥跳车时车轮脱空的临界速度计算值大大提高,10 mm错台跳车临界速度约60 km/h;跳车动力荷载与车轮悬挂方式、车速、跳车高度等有关,可由此控制轮载冲击系数;考虑车轮-路面接触长度后,桥头错台跳车的冲击系数仍较大。考虑车轮-路面接触长度后,桥头错台跳车的冲击系数仍较大,例如车辆以30 km/h以上速度通过10 mm错台时,冲击系数超过我国桥梁规范设计值,需引起重视。To analyze the dynamic load of vehicle in bridge-head bumping, a tire model considering the contact length between tire and road was presented, where the rolling trace of tire is also taken into account. By using dynamic finite element analysis, the load on tire when the vehicle passing through the staggered platform at bridge head was analyzed quantitatively. Numerical examples show that: the model accords well with the actual contact phenomena between tire and road, and the calculated dynamic load is less than the conventional value; the calculated critical speed when the vehicle getting down the staggered platform is much highe, for example, it is about 60 km/h when the vehicle geting down a 10 mm-high platform; the dynamic load is related to suspension pattern, vehicle speed and platform height, and the impact factor could be controlled; the impact factor is still high when the contact length is considered, for example, it is more than 0.3 when the vehicle passes through a staggered platform of 10 mm with a speed of 30 km/h, which is higher than that provided by Chinese design codes of bridge. It is worthy of our paying attention.

关 键 词：桥头跳车 动力荷载 接触长度 动力响应分析 冲击系数 

分 类 号：U441[建筑科学—桥梁与隧道工程]