Imitating Analysis Of Collision Happened In Bridges Induced By Earthquake And Study On The Measures Used For Anti-collision And Anti Falling-off Of Girder

Bridge is an important component of transport infrastructure,people pay more and more attention for the anti-seismic performance of it. The collision between adjacent girder or between the girder and abutment happened easily because of large displacement of girders during the earthquake. The collision not only cause collapse at the ends of girders, but also cause the unseating of girders. Therefore,it is important to study on the collision of bridge and corresponding measures.This paper choose a reasonable analysis measure about collision response and set up finite element model of bridges.And it calculate the collision response during the erthquke.The results show that the bridge occur collision easily during the earthquake. The force of the collision is great. And the interior of every collision is complicated. The possibility of collision and collision response are not the same for different bridges.By changing the parameters of the model it analyse the influence of the height of pier, forms of foundation and braking pier to collision response of bridges. The results show that the the possibility of collision and the force of the collision increases with the height of pier increasing. The possibility of collision adopted elastic foundation greater than that adopted rigid foundation. The collision response is influenced greatly by choosing different braking pier. By established the method of calculating damage ratio it give the assessment of concrete damage caused by collision.According to the results of collision response happened in bridges Induced by earthquake and the results of previous studies,it proposed some anti-collision and anti falling-off of girder measures.It is an effective way to reduce the collision between adjacent girders by setting up buffered device in the out space of gap and between the girder and abutment by setting up "Easily damaged" slide-block. Anti falling-off of girder measures mainly consist of inhibiting measure, anti falling-off of girder and expanded supporting zone. Steel member restricted longitudinal displacement of girder is an effective inhibiting measure.