Computation of the second fracture parameter in elastodynamics by the boundary element method

Abstract A path independent integral formulation for computation of dynamic T-stresses (the second fracture parameter) in a two-dimensional body with a stationary crack is presented. For solution of the crack problem the boundary element method (BEM) is used. The uniqueness of the BEM formulation of a general crack problem is established by a system of displacement and traction equations on the outer boundary of the body and the crack surface, respectively. The mutual M-integral expressed through the dynamic J -integrals provides sufficient information for determining T-stresses on the basis of a relation found between the M-integral and the T-stress. The integral representation of the T-stress is presented both in the time-domain and the Laplace transform-domain. The boundary layer and displacement field methods are used to test the accuracy of the suggested integral method. Numerical results are given for a rectangular plate with a central crack or an internally inclined crack.

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