# 대칭 Galerkin 경계요소법을 이용한 유한체 내에 존재하는 임의의 삼차원 균열의 해석

• Park, Jai-Hak (Department of Safety Engineering, Chungbuk National University) ;
• Kim, Tae-Soon (Korea Electric Power Research Institute)
• Published : 2004.03.01
• 56 4

#### Abstract

Many analysis methods, including finite element method, have been suggested and used for assessing the integrity of cracked structures. In the paper, in order to analyze arbitrary three dimensional cracks, the finite element alternating method is extended. The crack is modeled by the symmetric Galerkin boundary element method as a distribution of displacement discontinuities, which is formulated as singularity-reduced integral equations. And the finite element method is used to calculate the stress values for the uncracked body only. Applied the proposed method to several example problems for planner cracks in finite bodies, the accuracy and efficiency of the method were demonstrated.

#### Keywords

symmetric Galerkin method;three dimensional crack;finite element alternating method;stress intensity factor

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