Soil-Pile-Structure Interaction Analysis Based On Capacity Spectrum Method

As the development of Displacement-Based Seismic Design(DBSD) and Performance-Based Seismic Design(PBSD), Capacity spectrum method causes widespread attention and are studied widely. But it is uncommonly reported that Pushover is used in analysis of soil-structure interaction. This paper attempts to use Pushover analysis in analysis of soil-structure interaction.In this paper, capacity spectrum method is adopted to perform nonlinear static seismic response analysis for high-rise frame structures with pile group foundation resting on natural foundation soils. The substructure technique is adopted to simulate pile group with a group of springs, determine pile group stiffness with Davies method and establish the pushover model of soil-pile-structure interaction system. The Spectral Acceleration and the Spectral Displacement at performance points, base reaction and displacement of soil-pile-structure interaction model and rigid ground model under uniform load pattern and mode load pattern are analyzed. The differences of the results of two models under different earthquake intensities are discussed and some valuable results are obtained. Then, the P-y curve is used to simulate nonlinearity of the soil around the pile with a group of nonlinear springs. Capacity spectrum method advised by ATC-40 is adopted to perform three dimensional Pushover analysis of three different high-rise structures using ANSYS software. The results of three structures are discussed and some valuable conclusions are obtained.