The Development and Solution of Boundary Integral Equations for Crack Problems in Fracture Mechanics.

摘要

The elastostatic Boundary Integral Equation (B.I.E.) method is mathematically extended to include closed crack plane boundary value problems under general loading. The B.I.E. is formulated for a modified open crack geometry. By the formulation of a sum and difference state over the crack surfaces, a limit operation closing the crack is successfully performed. The resulting integral equation set is solved for two example problems possessing known solutions. The stress intensity factors, K(I), K(II), and K(III), and the resulting strain energy of the body are calculated and found to be accurate within 1% when compared to the analytical solution. The bent edge crack in a finite circular disk subject to mixed mode loading is investigated. Initial crack trajectories are predicted using the strain energy release rate criterion and compared to known results. (Author)