The Finite Element Analysis Of Load-bearing Characteristics For Composites Foundation With Cement-flyash-gravel Piles

The CFG pile composite foundation is the emerging foundation treatment technology, which has been widely used in engineering construction. Compared with the natural foundation, the CFG pile composite foundation belongs to the rigid-pile composite foundation. It can reinforce the foundation, reduce the foundation settlement, and increase the bearing capacity of foundation. The paper is in the background of project construction by the Tangshan Stainless Steel Limited Company where uses the CFG pile composite foundation to reinforce the foundation. In allusion to that the single CFG pile’s theory can not be applied to group piles’ theory, while it analyzes the working mechanism of composite foundation with group piles. The paper has important practical significance.The working mechanism of the CFG pile composite foundation, the influencing factors and calculation formula of the bearing capacity of composite foundation, and settlement theory have been analyzed systemataciallyAccording to geological data of engineering, the paper uses the finite element software of Midas GTS to analyze the CFG pile composite foundation from three aspects.(1) The 3D models of the CFG pile composite foundation are set up respectively, which have three affecting factors of the pile length, the pile spacing, and the pile diameter. The settlement in composite foundation with group piles and the pile stress and the pile side resistance and the pile-soil relative displacement are analyzed under different influence factors. The optimization scheme of the CFG pile composite foundation is determined.(2) The composite foundation load test is done, then it gets that the finite element simulation results and the test results are similar.(3) The 3D model of natural foundation is set up, and which is in comparison with the 3D model of the CFG pile composite foundation. Based on analyzing the two aspects of soil subsidence and ground stress, the reinforcement effect of composite foundation is validated.(4) Analyzing the optimized composite foundation under the load, the change rules are studied with settlement, pile stress and pile-soil stress ratio.