关键词: 振动, 动力特性, 自振频率, 振型, 冲击系数

Abstract: The vibration of bridge under the vehicle is caused by various vibrations.It is related with many factors,such as bridge dynamic characteristics,vehicle characteristics,speed,the car-bridge coupling function and the smoothness of the bridge deck.Through the systematic analysis and research on the measured data which cause the shock and vibration of Zhaojia bridge,it is found out that when driving on the non-large-span bridges,the speed at 10~20 km/h for the cross-bridge will result in more dynamic response,and the impact factor in the peak occurs at 10~20 km/h;when the bridge natural frequency is close to that of experimental cars with three-axis,the car-bridge coupling frequency vibration is easy to result in abnormal shock and vibration even on the deck with good circumstances.There are many factors leading to the abnormal shock and vibration of the car,however,that a variety of factors operate jointly is the decisive factor in abnormal vibration of the bridge.The combined effects of the factors are not simple weighted relations.When a variety of conditions are in the state of coupling match,the impact factor will increase doubly.

Key words: vibration, characteristic of dynamics, natural frequency, mode, impact factor