The Simulation And Analysis Of Large Scale Soil-Pile Raft Foundation-Frame Model For Dynamic Interaction

Based on the large-scale model test on soil-pile-structure interaction, as a part of the project aided by nature science national fund, analysis of soil-foundation -structure dynamic interaction (NO.50278033), some issues about modeling of soil-structure interaction system are discussed in this thesis. These issues mainly include simulation of soil infinity, selection of dynamic constitution model of material, simulation of the changing status nonlinearity on soil structure interface, meshing, using of symmetry principle and so on.Three-dimensional finite element analysis on large-scale test on soil-pile -structure interaction system is carried out in this thesis. In computational analysis, perfectly-plastic Mohr-Coulomb material and kinematic hardening Von-Mises material are chosen to simulate the non-linearity of soil and reinforced-concrete separately, and the changing status non-linearity on soil structure interface is considered by using contact function of MARC. Comparison analysis between computational results and test results shows that the basic frequency and curves in time-domain are coincident approximately, and it's verified that the simulation methods in this paper are rational and the model is feasible. The computational analysis shows that large error will occur when the material non-linearity of soil and reinforced-concrete is not considered in the calculation of interaction, and the changing-status non-linearity on soil-structure interface has some influence on the seismic response of structure.The seismic responses under the consideration of soil pile-raft foundation and structure interaction are discussed in this thesis which include acceleration response, strain response of pile, contact pressure on the pile-soil interface, sliding between pile and soil, effect of interaction on ground shock, the influences of parameters, such as soil property, excitation, and rigidity of structure on dynamic characteristics, seismic response and interaction effect of SSI system and so on are discussed.