Study Of Nonlinear Seismic Response Analysis Method Of Bridge Elevated Pile Foundation

In all kinds of civil engineering structures, there include lots of elevated pile foundations.It is very important to study the seismic performance of elevated pile foundation. In this paper,push-over analysis method of elevated pile foundation and some contributing factors werestudied. Fiber element model of elevated pile foundation was built and nonlinear performanceof elevated pile foundation in the earthquake was studied. The main contents of this paper areas follows:(1) Two elevated pile foundation models were built, which are equivalent consolidationmodel and soil-pile continuous beam model. Three lateral force modes are used in the processof push-over analysis. According to the results of push-over analysis for elevated pilefoundation, the suitable lateral force mode for elevated pile foundation in the push-overanalysis method was selected and the difference between two models was also compared.(2) In this paper, elevated pile foundations were analyzed use push-over analysis methoddue to different unconstrained lengths, and the P-△effect influence on push-over analysismethod was studied. P-△effect influence on capacity curve was expressed by capacityreduction ratio.(3) Elevated pile foundations were analyzed use push-over analysis method due todifferent m value, and the influence of m value on elevated pile foundation was obtained.Internal force of elevated pile foundation was also studied.(4) Elevated pile foundation model was built use P-Y curve method. The soil characterinfluence on structure internal force under horizontal force was studied. The soil charactercontains friction angle and density.(5) Fiber models of elevated pile foundation were built in the way of m method and P-Ycurve method. Nonlinear history analysis was completed due to different peak acceleration,and the differences between two methods were obtained.