作　　者： ; ; ; ;

机构地区： 广州大学

出　　处： 《应用力学学报》 2013年第2期160-166,298-299,共7页

摘　　要： 基于平稳随机振动理论和环境振动传播链条的随机性,将车辆简化为两自由度模型,考虑简支梁桥上车辆移动系统与桥面接触处不平顺产生的随机激励,并假设：车辆分布满足均匀分布;桥墩为基底固定的柱;地面为弹性半空间体,推导得到车-简支梁桥系统诱发地表振动响应的功率谱密度函数计算公式。通过参数分析和计算仿真的结果表明：简支梁桥系统对地表作用力的平均功率谱密度函数有三个峰值,车辆力学模型的自振频率决定了左起第一个峰值和第二个峰值的位置,桥梁的竖向刚度决定了平均功率谱密度函数的第三个峰值的位置,且频域分布密度主要集中在0~120Hz;频率为0~21Hz时,弹性半空间垂直加速度响应功率谱的幅值随Rayleigh波波速的增加而减小,频率大于31Hz后其幅值随Rayleigh波波速的增加而增大;通过与实测分析结果对比,可知本文理论分析结果能够大致反映环境振动频谱的分布范围（10~100Hz）,一定程度上验证了本文分析方法的正确性。 An analytical method for calculating the power spectral density(PSD) of traffic-induced ground vibration through the viaduct systems is presented.The vehicle is modeled as a two-DOF system with linear suspensions and tire flexibility,and the bridge is modeled as a continuous Euler-Bernoulli beam simply supported at both ends.The effect of road surface roughness is also considered.The theory of stationary random process is used to obtain expressions for the PSD of traffic-induced ground vibration when given the PSD of road surface roughness.The presented numerical results show that roughness class and vehicle velocity have considerable influence on the PSD.The PSD of traffic-induced force has three peak values,the vehicle model determines the first two peak values and the vertical stiffness of pier determines the third one.Dominant frequencies of PSD mainly range from 0Hz to 120Hz.In the frequency region [0-21Hz],the amplitude of the PSD of ground vibration increases as the wave velocity decrease,however it decreases in the frequency region [31Hz-∞Hz].The calculated result for the spectrum distribution region is roughly consistent with the measured results [10Hz-100Hz].

关 键 词： 交通工程 环境振动 随机振动 简支梁桥 功率谱密度 地表振动

领　　域： [建筑科学] [建筑科学] [交通运输工程]