The Seismic Response Analysis Of Concrete Filled Steel Tubular Arch Bridge

In the past years, the destructive earthquakes frequently occurred in the world, which brought great damage to the safety of people's life and property. The indirect disaster due to the earthquakes result in collapse of bridges regarded as the lifeline engineering, which will lead to more loss of life and property. Therefore, it is necessary to study and master the seismic response of bridges in order to establish reasonable seismic design system and take effective anti-seismic measures. In this thesis, choosing the Pedestrian Bridge of Chang' an University as the example which is a concrete-filled steel tube arch bridge, the seismic responses about this type bridge are investigated as follows:1,The dynamic characteristics is discussed under two different boundary conditions at the arch springing by model building with the fixed end condition and the pile-soil interaction condition. The calculating results indicate that the pile-soil interaction has little effect on the dynamic characteristics of such bridges.2,The acceleration response spectrum curve with different exceeding probability in the future 50 years according to the specific structure and construction sites geological characteristics of the pedestrain bridge of Chang' an University is choosed in this paper. Inputing the acceleration response spectrum curve along the longitudinal, transverse and multidimensional direction-horizontal combined vertical, the internal force and displacement of the control sections are gained.3,The seismic responses of long-span concrete filled steel tubular arch bridges to uniform excitation of earthquake are analysed. Structural seismic responses that seismic wave is inputted from vertical direction is discussed. Internal forces and displacements of structural crucial sections is larger in transverse seismic excitation than in longitudinal seismic excitation, and the influnce of vertical seismic excitation is not neglected. We find that the results gained by response spectrum analysis is too large, and it is necessary that the seismic checking computations is done combining with time-history analysis.4,By calculating the seismic response of long-span concrete filled steel tubular arch bridge considering travelling wave effect by inputing different velocities of seismic wave and comparing the results under the coincident earthquake excitation, we reach the conclusion that the influence of travelling wave effect to the seismic response of the bridges is very small.