Researches On Wind-vehicle-bridge Coupled Vibration Of Ji Jiang Yangzte River Combined Highway And Railway Suspension Bridge

Suspension bridges use high strength steel bars to bear tension, and they have merits such as long span ability、reasonable stress condition and relatively low budget. And they are always favorable choices when the bridge span exceeds600meters. Suspension bridges are flexible structures, and have low rigidity, so it is necessary to do researches on wind-vehicle-bridge coupled vibration. This article takes Ji Jiang Yangtze River Bridge (located in Jin Jiang district, Chong Qing city; with a span arrangement of (50+600+65) m) as engineering background, analyzes vehicle-bridge coupled vibration of suspension bridges under wind load. The major work and results are as follows:1. Development situations of suspension bridges and combined highway and railway bridges in and abroad China are introduced, brief introduction of wind-vehicle-bridge coupled vibration research is also presented.2. Based on the principle that dynamics total potential energy of elastic system keeps unchanged and the matrix matching principle. The vehicle model,a whole bridge finite element analysis model of Ji Jiang Bridge and the vehicle-bridge system vibration equation are established.3. Numerical wind tunnel technology is used to analyze the aerostatic coefficients of the vehicle,the bridge girder and the vehicle-bridge girder system model. The wind stochastic field of Ji Jiang Yangtze River Bridge is simulated numerically.4. The vehicle and bridge responses of vehicle-bridge system for Ji Jiang Yangtze River Bridge under windless condition are analyzed, the results show:the maximum values of all the indicators for the bridge responses are within the admissible value bounds of the relevant codes, thus satisfy safe driving requirements.5.Dynamics simulation analysis are done for the wind-vehicle-bridge system coupled vibration of Ji Jiang Yangtze River combined highway and railway suspension bridge; the researches show:the bridge satisfies all the vehicle safe and comfortable driving requirements when the wind speed is less than25m/s;it meets the train operation control procedures standards under strong wind both in Japan and China; this indicates that the strong wind effection on the train moving won’t become the controlling factor of the whole line.