Analytical Calculation of Stress Intensity Factors for Unequal Cracks Emanating from a Circular Hole in an Infinite Plane

Document Type : Research Article

Authors

Department of Mechanical Engineering, K. N. Toosi University of Technology, Tehran, Iran

Abstract

Thin plates are used in marine and aerospace structures. Geometric defects in components and industrial structures usually occur intentionally or unintentionally which hole is one of them. It is common that a crack initiate in the areas of stress concentration. Even if the crack is relatively small, it propagates and can lead to a dangerous situation. Stress intensity factor is one of the important parameters of the crack behavior. In this paper, by using the analytical solution of Muskhelishvili and finding suitable conformal mapping, behavior of two unequal and aligned cracks emanating from a circular hole is investigated. The effect of parameters such as load orientation, crack length and etc. is studied. The hole and the cracks are assumed to be traction free. The infinite isotropic plane is subjected to a uniform tensile loading at infinity in an arbitrary direction. To ensure the accuracy of the method, results are compared with some specific problems. In this paper, an explicit formula based on the geometric parameters of the problem is presented for stress intensity factor. Also and are obtained for various loading and cracks length.

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