Xiangjiang River Bridge Sanchaji Self-anchored Suspension Bridge Seismic Response

In recent years, self-anchored suspension bridge has made an appeal in field of engineering. However, form the document that has exited, there is few research on self-anchored suspension bridge, especially its dynamic behavior and seismic response. In this paper, San Cha Ji Xiang River Bridge, a self-anchored suspension bridge with the main span of 328m, is an example for the analytic solution of dynamic behavior and seismic response. The main finished work covers the following aspects:1. With the function of coupling, stress stiffening, initial stress in ANSYS, reasonably simulate boundary conditions and initial state of the self-anchored suspension bridge, thereby establishing its space finite element model. The vibration frequencies and corresponding vibration mode is given by using the model. At the same time, the effects caused by dead load, geometric nonlinearity, initial tension in the main cables and suspenders, Pile - soil interaction, variety of structure parameters are computed.2. The seismic response of the self-anchored suspension bridge is computed with response spectrum analysis method. The effects caused by input ground motion, the higher vibration modes, modal composition, vertical component of the earthquake are discussed.3. The method generating artificial ground motion in time history analysis is researched. Much attention has been paid to the method generating artificial ground motion with trigonometric functions and a program based on the method is compiled to generate artificial ground motion. According to the ground condition of the self-anchored suspension bridge, three artificial ground motions are generated for calculating the seismic response of the bridge with time history analysis.4. Three artificial ground motions are used as input earthquake to calculate the seismic response of the suspension bridge with time history analysis. The seismic response computed with time history analysis is compared to that computed with response spectrum analysis method, the effects caused by vertical seismic component, wave passage effect, geometric nonlinearity, damping is compared.