The Research On Three-dimensional Nonlinear Numerical Simulation Analysis Methods About Lateral Load Of Pile Raft Foundation

The pile raft foundation is made up by pile and raft foundation. Raft is closely combined with pile foundation, raft thickness and stiffness in a great influence on the pile raft foundation differential settlement, etc. Pile foundation belong to artificial foundation, the distribution of pile foundation is important for lateral bearing capacity and vertical bearing capacity, etc, With the basement of the building and high-rise building using the pile raft foundation very common. If base on the upper load is very big, can not meet the standards required by the common foundation and soil, the pile raft foundation is a very good choice. At present, on the behavior of the pile raft foundation under horizontal load work study, mostly through the actual experiment analysis and numerical simulation analysis and theoretical analysis under various assumptions. Actual experiment analysis usually consume a large amount of manpower material resources, takes much time but is also longer, process the data result also to have certain limitations. Along with the continuous development of science and technology and improve the numerical simulation which spend less time and manpower cost little and results are accurate, makes the finite element technique in the study of the pile raft foundation work character, has been more and more used. As a result, with 3D finite element to simulate the force performance analysis of the pile raft foundation, and also gradually become a development trend.This paper gathers the pile raft foundation work background, working principle and research status at home and abroad, and expounds the domestic pile raft foundation of conventional design method.Then, this paper, by using the finite element software ANSYS as a platform to simulate the pile raft foundation in situ test, mainly aimed at the nonlinear response of pile raft foundation transverse mechanics analysis. In ANSYS model, consider the force as well as the upper and lower symmetry of the model and the selection of the material constitutive relation of soil and the rationality of the meshing boundary conditions and ANSYS model of processing and interface state of nonlinear factors such as pile-soil, a model is established and validates the correctness of the model. Based on the correct model, in this paper, the pile raft foundation under horizontal load of each pile, the bending moment of pile, pile body sway work properties such as load sharing ratio were studied. Based on the correct model, in this paper, the pile raft foundation under horizontal load of each pile, the bending moment of pile, pile body sway work properties such as load sharing ratio were studied. Based on the model data, by changing the parameters of the model such as the parameters of the pile length, pile spacing and pile diameter is an accurate reflection of the working mechanism of pile-supported raft foundation, has good reference value for engineering. The ANSYS calculated results comparing with m method to calculate the results, The results show that the three-dimensional finite element numerical simulation can more accurately reflect the actual situation of the pile raft foundation.