The Study On The Seismic Response Analysis And The Seismic Reduce And Isolation Research For Concrete Filled Steel Tubular Arch Bridge

In recent years, high speed railway construction is developing fast, and the bridge accounts for a large proportion of it. The form of bridge structures changes quickly. The concrete filled steel tube arch bridge with high bearing capacity, strong spanning ability and elegant form now gradually be used in railway. Over the past decade, high magnitude and large destructive earthquake disasters occurred more and more frequently, the concrete filled steel tube arch bridge has big span, high center of gravity and huge mass, the question of seismic response is very highlighted, therefore, study on seismic mitigation and seismic isolation in the railway bridge has important significance.On the bases of HuJianWan concrete filled steel tube arch railway bridge, using the finite element analysis software MIDAS established the dynamic analysis finite element model. The main results of this paper are presented as follows:1. Analyzed the dynamic characteristics of the bridge, discussed the influence of arch inclination angle and the different forms of suspender on dynamic characters. The result shows that arch inclination angle enhance the transverse stiffness; the incline suspender enhance the internal stiffness.2. Analyzed the seismic response characteristics of the arch bridge by method of response spectrum analysis and time-history analysis and compared the result of the two methods. The result shows that there is no special rule of the two methods; we should combine the results of the response spectrum analysis and the time-history analysis considering all the most unfavorable combination of seismic response component to guide design.3. Discussed the isolated effect of LRB.Introduce the parameters calculation method of LRB, simulated the two-way-coupling model of LRB in MIDAS. Analyzed the influence of LRB’s parameters like lead-diameter, stiffness ratio and rubber-diameter on seismic isolation effect; discussed the isolated effect by seismic waves, the height of bridge piers. The result shows that after installing the LRB, the strcture forces have a great degree of decline, each pier share seismic force together, the seismic force distribute more uiniform. The LRB isolation effect is obvious.