Analysis On Random Vibration Of Highway-Bridge Structure

The random vibration for highway-bridge structure is a problem which can only use the statistic system to solve and we can not use the affirmatory method to solve the problem. In this paper, the author suggests a new method to solve random vibration of the vehicle-bridge coupled system: going ahead on the basis making use of the finite element software being applied or used universally, the author makes the vehicle vibration under random stimulation into the form of force, and carry out a analysis on the changing law of the vehicle-bridge coupled system under the influence of the random factor belong to the vibration aspect.In this discussion, the vibration equation of the vehicle model with one freedom is built, and the vehicle-bridge coupled vibration equation is also built. The author analyzes the effect of many random factors on vehicle-bridge coupled system. For example, on the basis adopting the probability model of the road surface roughness, the model of the surface roughness of bridge-deck is built;The suppuration model of the vehicle's bridgehead jumping or the damage of bridge-deck is also built, and the vehicle-bridge coupled vibration equations under the influence of the two random factors are also built separately.In this discussion, the author respectively calculates the dynamic effect of five bridges on the aspect of the surface roughness of bridge-deck or vehicle's bridgehead jumping or the damage of bridge-deck, and analyzes the law of vehicle-bridge coupled system under the influence of the surface roughness of bridge deck, and analyzes the law of vehicle-bridge coupled system under the influence of the vehicle's bridgehead jumping or the damage of bridge-deck. At last, the author respectively argues on the changing law of vehicle-bridge coupled system under the influence of vehicle's speed or the initial vibration state at the time of vehicle running on bridgehead or the degrees of the surface roughness of bridge-deck or the altitude difference between road surface and bridge surface or the physical location of the damage of bridge-deck on the bridge.