Seismic Analysis Of Long-span Continuous Bridge Under Non-uniform Excitation

Normally, analyzing the seismic response of a bridge assumes that the seismic vibrations of all bridge piers’bottoms are the same, this assumption exists big calculation errors, in order to make the results of the finite element software is more appropriate to the actual situation, this paper uses the non-uniform input method to analyze continuous beam bridges.Using the Garden No.1fast continuous girder bridge in Dandong-Dalian fast Railway as the research object, using ANSYS finite element analysis software analyzed the impact of the shearing stress of the fixed pier’s bottom, the tension stress of the fixed pier’s bottom and the maximum relative displacements between two piers by considering traveling wave effect, by loading the same intensity level and different seismic waves, founding the reason why there are differences between results of the numerical response. The results show that:by loading the non-uniform and the same intensity levels of different seismic waves, the shearing stress of the fixed pier’s bottom, the tension stress of the fixed pier’s bottom and the maximum relative displacements between two piers exist discrete nature; Traveling wave effect brings significant impact on the shearing stress of the fixed pier’s bottom, the tension stress of the fixed pier’s bottom and the maximum relative displacements between the piers. The height of a bridge’s pier influence the traveling wave effect, but the extent is little; The traveling wave effect increases the maximum relative displacements between two continuous bridge’s piers, The height of a bridge’s pier influence the traveling wave effect, but the extent is little; Chang the entering direction of the wave along the longitudinal direction of the bridge, the influence’s degree of the shearing stress of the fixed pier’s bottom, the tension stress of the fixed pier’s bottom and the maximum relative displacements between the piers is small.In order to verify the ANSYS software’s calculation results are right, go a analytical analysis, contrasting the results of the analytical analysis with the ANSYS software’s calculation results, proved ANSYS software’s calculation results are right. By the results of the analytical analysis, found that the shearing stress of the fixed pier’s bottom being influenced by the surface velocity of seismic waves, the significant of seismic waves and the natural frequency of a structure.To study the responses of different spans’continuous bridges under traveling wave effect, contrasting the Tang Chi continuous girder bridge in Dandong-Dalian fast Railway with the Garden No.1continuous girder bridge in Dandong-Dalian fast Railway, finding that:two different spans’continuous bridges, the changed degree of the shearing stress of the fixed pier’s bottom, the tension stress of the fixed pier’s bottom and the maximum relative displacements between the piers by traveling wave effect is different.