考虑车体柔性的车桥耦合系统建模与分析方法  

Modeling and dynamic analysis method of vehicle-bridge coupling system considering car-body flexibility

作　　者：李奇[1] 吴定俊[1] 邵长宇[2] 

机构地区：[1]同济大学桥梁工程系,上海200092 [2]上海市政工程设计研究总院,上海200092

出　　处：《振动工程学报》2011年第1期41-47,共7页Journal of Vibration Engineering

基　　金：国家自然科学基金(50908178);上海市优秀学科带头人计划基金(07XD14204)

摘　　要：铁路车辆车体的柔性是其固有属性。假设车体为柔性体而轮对、构架为刚性体,并将车辆视为通过赫兹接触弹簧支撑在轮轨接触界面之上的空间结构。在通用有限元软件中采用刚度极大的梁单元建立轮对和构架模型,而采用刚度适当的梁单元建立车体模型,并利用弹簧单元模拟第一系和第二系悬挂线弹性刚度。将车辆悬挂系统的阻尼力、作用在轮对上的轮轨力作为虚拟力施加在车辆子系统上,将作用在轨道上的轮轨力类似地作为虚拟力施加在桥梁子系统上。对车辆线弹性有限元模型以及桥梁有限元模型进行模态分析,结合采用模态叠加法和拟力法形成车辆-桥梁耦合系统运动方程,运用迭代方法求解系统振动响应。对高速列车通过多跨简支梁时的刚性和柔性车体振动现象分别进行数值仿真再现,既验证了提出的计算方法,也表明考虑车体柔性对共振时车体加速度计算值有较大影响,而对桥梁加速度基本无影响。The car-body of a railway vehicle is flexible in nature.Car-body flexibility is considered while the wheel-sets and the bogies of a railway vehicle are regarded as rigid bodies in the proposed vehicle-bridge dynamic interaction analysis method.The vehicle is considered as a spatial structure supported on the wheel-rail interface through Hertz nonlinear spring.The wheel-sets and bogies are established by rigid beam elements coded in general finite element software.The car-body is modeled by flexible beam elements,and linear stiffness of the primary and the secondary suspensions is modeled by spring elements in the same software.The damping forces of the suspensions and the wheel-rail interaction forces on wheel-sets are treated as pseudo forces acted on the vehicle subsystem.The wheel-rail interaction forces on the rails are similarly treated as pseudo forces acted on the bridge subsystem.Mode analyses are conducted based on finite element models of the vehicle and the bridge.And then mode superposition method associated with pseudo force treatment is applied to establish equations of motion of the coupling vehicle-bridge system.An iterative scheme is used to solve the equations of the system.The proposed method is firstly verified by a numerical example,and then the vibration of the car-body with different flexibility is numerically simulated when high speed train traverses multi-span simply supported bridges.The car-body acceleration is found to be underestimated if its flexibility is not considered,especially when flexible car-body resonance phenomena occur.Nevertheless,the bridge acceleration is hardly affected by flexible car-body vibration.

关 键 词：车辆 桥梁 动力相互作用 柔性车体 共振 

分 类 号：TU311.3[建筑科学—结构工程] U270.2[机械工程—车辆工程]