Finite Element Analysis Of The Vertical Bearing Behavior Of Group Piles Under Combined Compression-Uplifting Loadings

Group piles under combined compression-uplifting loadings as a sort of footings has a wide range of applications for a variety of high rise buildings and bearing buoyancy buildings, so the behavior of them has gradually increased in the geotechnical engineering. Though a large number of them have been used, their load transfer mechanism is not distinct.In this paper, the uplift and downward piles load-bearing properties in isotropic soil are studied by the finite element method, based on a three dimensional model of pile-soil mass.The Mohr-Coulomb model and the contact surface model are adopted to simulate the characters of soil and the interaction of pile and soil respectively, and use the one of finite element analysis software ABAQUS to analyze this model.The model is able to analyze single pile-soil mass system under the uplift load, and under the downward load, and contrastively analyze single pile-soil mass system under both the uplift load and the downward load.This paper has researched the effecting factors subjected to load-displacement, the characters lateral friction resistance and axial force curves of piles under both uplift loads and downward loads.The model can be able to analyze pile groups under the uplift load and the downward load in the same time. Then discuss the behavior of uplift piles and downward piles in several conditions.The research of this paper has obtained a series of efforts, and it has figured out that the behavior of uplift piles and downward piles is different. It can provide references for the realistic engineering design of uplift and downward piles.