Mixedmode stress intensity factors of a threedimensional crack in a bonded bimaterial

• Published in: Engineering computations 2008-04, Vol.25 (3), p.251-267
• Main Authors: Qin, T.Y., Zhu, B.J., Noda, N.A.
• Format: Article
• Language: English
• Subjects: Boundaryelements methods; Composite materials; Stress materials
• ISSN: 0264-4401
• DOI: 10.1108/02644400810857083

Purpose This paper aims to calculate the mixedmode stress intensity factors SIFs of a 3D crack meeting the interface in a bimaterial under shear loading by a hypersingular integral equation HIE method, And further to assess the accuracy of numerical solutions for the mixed mode SIFs along the crack front. Designmethodologyapproach A 3D crack modeling is reduced to solving a set of HIEs. Based on the analytical solutions of the singular stress field around the crack front, a numerical method for the HIEs is proposed by a finitepart integral method, where the displacement discontinuities of the crack surface are approximated by the product of basic density functions and polynomials. Using FORTRAN program, numerical solutions of the mixedmode SIFs of some examples are presented. Findings The numerical method is proved to be an effective construction technique. The numerical results show that this numerical technique is successful, and the solution precision is satisfied. Research limitationsimplications This work takes further steps to improve the fundamental systems of HIE for its application in the fields of arbitrary shape crack problems. Propose several techniques for numerical implementation, which could increase the efficiency and accuracy of computation. Practical implications Whenever there is a structure containing the 3D crack, the analysis method described in this paper can be utilized to find the critical configurations under which the structure may be most vulnerable. In such cases, the strength predictions would be safer if the crack could be taken into account. Originalityvalue This paper is the first to apply HIE method to analyzing the mixedmode crack meeting the interface in 3D dissimilar materials. Numerical solutions of the mixedmode SIFs can give the satisfied solution precision.