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arXiv · 0812.4529

Symmetric and skew-symmetric weight functions in perturbation models of 2D interfacial cracks

A. Piccolroaz·G. Mishuris·A. B. Movchan
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Abstract

In this paper we address the vector problem of a 2D half-plane interfacial crack loaded by a general asymmetric distribution of forces acting on its faces. It is shown that the general integral formula for the evaluation of stress intensity factors, as well as high-order terms, requires both symmetric and skew-symmetric weight function matrices. The symmetric weight function matrix is obtained via the solution of a Wiener-Hopf functional equation, whereas the derivation of the skew-symmetric weight function matrix requires the construction of the corresponding full field singular solution. The weight function matrices are then used in the perturbation analysis of a crack advancing quasi-statically along the interface between two dissimilar media. A general and rigorous asymptotic procedure is developed to compute the perturbations of stress intensity factors as well as high-order terms.

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A. Piccolroaz, G. Mishuris, A. B. Movchan. 2009-09-29. Symmetric and skew-symmetric weight functions in perturbation models of 2D interfacial cracks. https://doi.org/10.1016/j.jmps.2009.05.003

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