【作者】 林家浩； 张志超；

【Author】 Lin Jiahao Zhang Zhichao (Department of Engineering Mechanics,State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian University of Technology,Dalian 116023,China)

【机构】 大连理工大学工程力学系工业装备结构分析国家重点实验室；

【摘要】 本文研究了考虑轨道高低不平顺的车桥耦合系统垂向非平稳随机振动。车辆采用具有两系悬挂10自由度的四轮模型,桥梁采用Bernoulli-Euler梁单元有限元模型。假设轨道高低不平顺为均匀调制演变随机过程,并充分考虑车轮间的相位差,采用虚拟激励法(PEM)将轨道不平度精确地转化为一系列垂向简谐不平度的叠加,亦即将轨道施加于车辆的非平稳随机激励转化为确定性激励,大大简化了运动方程的求解。在此基础上采用能够更真实地模拟车轮作用力在时间域和空间域上连续变化的精细积分法(PIM)来进行数值积分计算。最后通过算例给出了耦合系统响应统计值变化的时程曲线,分析了车辆行驶速度和轨道不平顺对于系统随机响应的影响。数值计算表明:本文发展的虚拟激励-精细积分法能够高效精确地进行车桥耦合系统的垂向非平稳随机振动分析:行车速度对于系统的随机振动响应影响较大,不容忽视。更多还原

【Abstract】 Vertical non-stationary random vibration of vehicle-bridge coupling systems subjected to track irregularity excitations is investigated.The vehicle is modeled as a four-wheel mass-spring-damper system with two layers of suspension systems possessing 10 degrees of freedom.The bridge is modeled as an elastic Bernoulli-Euler beam,and the track irregularity is assumed to be a uniformly modulated evolutionary random process with the phase-lags between the wheels taken into account. Pseudo-Excitation Method(PEM) is applied to transform the random surface roughness into the superposition of a series of deterministic pseudo harmonic surface unevenness and thus simplifies the solution of the non-stationary random vibration equations considerably.Meanwhile the precise integration method(PIM) is developed to simulate the continuous varying of the vehicle loads both in the time and space domains in the numerical integration process.Numerical examples are given and the significant influence of the vehicle speed on the system random responses are discussed.The proposed method shows satisfactory efficiency and accuracy.更多还原