作　　者： ; ; ; ; ;

机构地区： 淡江大学

出　　处： 《工程力学》 2013年第5期227-233,237,共8页

摘　　要： 针对环境振动波传播链条系统的随机性,基于平稳随机振动理论,将车辆简化为两自由度模型,考虑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及地面为弹性半空间体,推导得到桥墩对地面作用力功率谱密度函数、地表响应功率谱密度函数和建筑结构响应功率谱矩阵,建立起公路简支桥系统诱发环境振动随机响应的完整分析理论。通过数值仿真分析,表明简支梁桥系统对地面作用力的平均功率谱密度函数有3个峰值,车辆力学模型的自振频率决定了第1个和第2个峰值的位置,桥墩竖向刚度决定了平均功率谱密度函数第3个峰值的位置;随响应点与荷载作用点距离的增加,垂直加速度响应功率谱的幅值在减少,且高频部分更加明显;结构振动特性对环境振动波在建筑结构内的传播有显著影响。 An analytical method for calculating the power spectral density （PSD） of the traffic-induced force acting on the ground, ground vibration, and dynamic response of building induced by the viaduct systems is presented. The vehicle is modeled as a two-DOF system with linear suspensions and tire flexibility, the bridge as a continuous Euler-Bemoulli beam simple supported at both ends, and the ground as an elastic half space. The effect of road surface roughness is also considered. The theory of a stationary random process is used to obtain expressions for the PSD of traffic-induced force, ground vibration and building vibration, when the PSD of road surface roughness is given. The obtained numerical results show that the PSD of a traffic-induced force has three peak values, the vehicle determines the first two peak values and the vertical stiffness of pier determines the third one. The amplitude of the PSD of a ground vibration decreases as the distance between the loading position and response point increases, and this reduction is obvious particularly in the high frequency region. In addition, the influence of structural properties on the propagation of an environmental vibration inside building is obvious.

关 键 词： 结构工程 环境振动 平稳随机过程 简支公路桥梁 功率谱密度

领　　域： [建筑科学] [理学] [理学]