Finite Element Analysis For Interaction Of Superstructure,Raft And Rigid Pile Composite-Foundation Via Object-oriented Approach

Nowadays, Composite foundation is one of the most widely used soil improvement technologies. With higher and higher demand to soil improvement, composite foundation technology is developing continuously. Rigid-pile composite foundation is a new method of ground improvement, which is defined to be used to support upper loads together by reinforced concrete piles (or concrete piles) and soil around. Rigid-pile composite foundation has been developed recently because of its high bearing capacity, little settlement, wide adaptation, good economical and social benefit.With the combination of finite element method and related literature at home and abroad, this paper sets up a coupled non-linear numerical approach for the rigid-pile composite foundation-raft system by 2D 8-node Mindlin element, 3D 20-node iso-parameter and 3D 16-node interface element. The elastic material is used to simulate the piles, cushion, raft and superstructure, and the nonlinear elasticity Duncan-Chang model is used to simulate soil as well as interface element method is introduced in between piles and soil.The Object-Oriented programming of finite element software OOPFE (Object-Oriented programming of finite element) with VC++ is developed. First, uses the ANSYS program to pre progress. And then, uses OOPFE and Excel to post progress.The character of raft settlement and moment, stress distribution of rigid-piles and soil, pile-soil stress ratio is analyzed. Case study show that the object-oriented model presented in this dissertation is believable and feasible.