Research On Element Free Garlerkin Method And Its Applying In Mechanic Analysis Of Pile Under Inclined Loads

The research on the mechanic analysis and design theory of pile, in particular,pile under inclined loads has been becoming one of the most important problems in civil engineering field at all times. According to the current codes in our country, pile under inclined loads were analyzed respectively under vertical and horizontal loads with the results superposed, and there were some deficiencies in this computational model. Thus, combining with the engineering characteristics of pile under inclined loads and working in the element free method reflecting the complex boundary conditions, deep research for mechanic analysis of pile under inclined loads had been doing.Firstly, on the basis of discussing the principle of the Element Free Galerkin Method (EFGM) based on variational principle and modified variational principle, the problems of the essential boundary conditions and the displacement continuity on the material discontinuous interface had been solved by Lagrange multipliers method and penalty method. Moreover, by making use of the hybrid iterative algorithm i.e. incremental initial stress method in the EFGM, the solving method for the elastic-plastic nonlinear problems had been established and an EFGM program was developed which could do linear elastic analysis, elastic-plastic analysis for homogeneous and inhomogeneous material.Secondly, according to the characteristics of mechanic analysis of pile under inclined loads, the EFGM for analysis of internal force of pile had been stressly studied in details by using the EFGM program mentioned. The method could consider complex load conditions (such as horizontal, vertical and inclined loads). Variation characteristics of internal force & deformation and the failure modes of pile under inclined loads were researched by the EFGM analysis of a rigid pile and a flexible pile. By the comparison of the EFGM results with the m-method results, it can be concluded that the EFGM is correct and superior to other methods and the EFGM used in mechanic analysis of pile under inclined loads was of theoretic and practical value, although the analysis results indicated that there were still some problems which should be urgently solved.