Abstract: The vibration balance equation for a quarter vehicle and bridge were derived with the employment of d’Alembert principle. The bridge surface roughness was obtained by trigonometric series method. The effects of bridge surface roughness,vehicle velocity and vehicle parameters on impact coefficient were studied by numerical method. The research shows that the influence due to the bridge surface roughness is significant; impact coefficient is fluctuating with increasing vehicle velocity; reasonable vehicle parameters can decrease impact action to the bridge; natural frequency is also an important factor to impact coefficient.

Key words: d’Alembert principle, trigonometric series method, bridge surface roughness, impact coefficient, vehicle parameters

摘要： 应用达朗贝尔原理推导了1 /4 车辆模型和桥梁的振动平衡方程； 采用三角级数法生成各级桥面不平度序列； 用数值方法分析了桥面平整度、车速及车辆参数对桥梁冲击系数的影响。结果表明: 桥面不平度对桥梁冲击系数影 响很大； 冲击系数随着速度的增加而发生波动； 合理的车辆参数可以减小对桥梁的冲击作用； 车辆固有频率同样是 影响冲击系数的一个不容忽视的因素。

关键词: 达朗贝尔原理, 三角级数法, 桥面不平度, 冲击系数, 车辆参数