跳车冲击力作用下车桥耦合动力学数值分析  

Dynamic Analysis of Vehicle-bridge Interaction Considering the Action of Jump Impacting Force

作　　者：樊建平[1] 曹高威 胡隽[1] 廖碧海[1] Jianping Fan Gaowei Cao Jun Hu Bihai Liao(School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, Wuhan , 43007)

机构地区：[1]华中科技大学土木工程与力学学院,武汉430074

出　　处：《固体力学学报》2016年第6期553-558,共6页Chinese Journal of Solid Mechanics

基　　金：国家自然科学基金项目(51678264)资助

摘　　要：考虑到传统的Hertz弹簧模型进行车桥耦合动力学分析存在诸多问题,基于简单的车桥耦合模型,导出了车桥耦合与非耦合动力学方程.考虑轨道周期和随机不平顺情况,车辆在不平顺轨道曲线上运行时,当离心力大于车辆自重时,自动确定车辆的起跳时间和起跳高度.起跳后的车辆在重力作用下,将重新回到梁上,同时对梁有一冲击作用力.文章假设了此冲击力的作用规律,并由有限元模拟确定冲击力系数.通过自编程序,对单轴行车简支梁进行了数值计算.数值分析结果表明,考虑跳车冲击力的动力模型能够更加精准地反应车桥耦合振动特征,且本模型首次给出了跳车高度.考虑轨道具有相同幅值的周期不平顺和随机不平顺时,轨道随机不平顺将导致桥梁,尤其是车辆的响应更大,舒适性更差或结构更危险,在车桥耦合动力学分析中应重点关注.There exist a series of problems when using the traditional Hertz spring model for dynamic analysis of vehicle-bridge coupling vibration. Based on the simple model for both vehicle and bridge, the equations for coupled and uncoupled vehicle-bridge dynamics are derived. Usually, the rail shows some irregularities, such as the periodic and stochastic irregularities. When the vehicle moves on this kind of rail, it will jump if the centrifugal force is greater than the weight of the vehicle. Afterwards, the vehicle will fall back onto the beam under the action of gravity. During this course, the beam is subjected to an impact force. The paper proposed the role of impact laws and determined the impact parameters using the finite el- ement simulation. On the platform of MATLAB, the program code was edited for the single-axle vehicle model moving on a simply-supported beam. The numerical results showed that the vehicle-bridge coupling vibration was more accurately characterized using the dynamic model with the impact force of vehicle considered. Furthermore, the model given in this paper can denote the jump height of the vehicle. For the ca- ses of periodic and stochastic irregularities with the same amplitude, the stochastic irregularities cause larger responses for both the bridge and the vehicle, leading to reduced riding comfortableness as well as less safety. For this reason, we should pay more attention to the stochastic irregularities in vehicle-bridge cou- pling dynamic analysis.

关 键 词：不平顺 车桥耦合 跳车 接触 冲击力 

分 类 号：U441.7[建筑科学—桥梁与隧道工程] U211.3[交通运输工程—道路与铁道工程]