Research On Coupling Model Of Stress Field And Seepage Field By EFM

Element-free method(EFM), a new numerical method for engineering, has great advantages comparing with the finite element method(FEM). In this paper, combining with the key project of the academician development fund of Hohai University, the basic theory of EFM and its application in solving the stress field and simulating crack propagation are studied. The model of solving seepage field and the coupling model of stress field and seepage field are developed by use of EFM. The main contents are as follows:(1) The basic theory of the moving least square method (MLSM) is introduced. Then the differences between the approximations of MLSM and finite element method(FEM) are discussed, and the coupling methods of them are briefly introduced.(2) The basic theory of EFM for solving the stress field and the realizing process of tracing crack propagation with EFM are introduced. The correctness of the program is validated with some examples. And it is used for analysing the stress and stain of Dongfanghong gravity dam. In addition, the stress result calculated by EFM is compared with the one by FEM.(3) The basic theory of EFM is studied for solving the seepage field in detail, and the interrelated formulas of penalty method for dealing with the seepage boundary are deduced detailedly. A computation program is developed for solving the seepage field with free surface, and it is proved that the method and program is valid and efficient by many examples.(4) The basic theory of coupling analysis of seepage field and stress field is studied. By using iteration decoupling technique, a coupling model of the stress field and seepage field is established, and the corresponding program is developed. It is verified that the coupling analysis results by the EFM is conformed to the general law.