考虑突发断缆事件的车桥系统动态行为分析方法

To achieve operational safety analysis of cable system bridges in the abrupt cable-breakage events, a dynamic behavior analysis method for vehicle-bridge system considering the updating of modal information and time-varying step size was proposed, considering the entire process characteristics of the abrupt cable-breakage events. By refining the calculation step and considering the change of bridge modal information in the process of cable breaking, the refined calculation of dynamic response of vehicle-bridge system under cable-breaking event was realized. Based on the proposed method, numerical simulations were conducted to analyze the impact of cable breakage on the dynamic behavior of the vehicle-bridge system using a cable-stayed bridge example. The results show that single cable breakage can cause a 2. 56% frequency change of the bridge, and the dynamic response of the girder section caused by the single cable breakage can increase up to 80%-140%. The dynamic amplification effect of the cable force at the transverse symmetric position of the broken cable is the most significant, reaching 2. 16. The vertical acceleration amplitude of vehicle body is about 10 times of that without broken cable, which is the main factor threatening driving safety.