鉴于车体点头刚度对双链式悬索桥动态响应的影响很小,采用单个移动质量-弹簧-阻尼模型模拟车辆模型,应用达朗贝尔原理和位移协调条件,推导出车-桥系统耦合振动的运动方程.考虑几何非线性及桥面不平度因素,就车辆沿桥纵轴向中心行驶和偏心行驶两种工况,探讨单个移动车辆荷载对双链式悬索桥振动响应的影响.针对车辆不同行驶速度,就该类悬索桥车辆冲击系数进行分析,理论分析与试验结果比较吻合.
Taking into account the fact that the nodding stiffness of vehicle body had little effect on the dynamic responses of double cable suspension bridge, a single movable mass-spring-damper model was adopted to simulate the vehicle model. The motion equation of vehicle-bridge coupling vibration was derived by using D'Alembert principle and the conditions of displacement compatibility. The influence of loads of single moving vehicle on the vibration responses of a double cable suspension bridge was explored on the basis of considering the geometric nonlinearity and irregular profile of the bridge pavement and two types of vehicle loading conditions, namely moving along the central and eccentric longitudinal bridge axis. The impact coefficient of vehicle velocity was analyzed for this type of suspension bridge. Theoretical analysis was consistent well with experimental result.