Study of stress intensity factor of radial crack developed from the edge of a circular hole under combined normal and shear loading

Abstract

In the present work the stress intensity factor of radial crack emanating from the edge of a circular hole subjected to combined normal and shear loading has been investigated numerically. This work has been done following a new approach in which stress intensity factor can be calculated without calculating the shape factor, which depends on the crack geometry and loading condition. For each of the crack geometry, such as crack length, hole radius and for each of the loading condition shape factor has to be determined separately and its determination require extensive numerical computation. In this work stress intensity factor has been determined by calculating the shape factor in a more general form. Here stress intensity factor is related to the solution of a Fredholm integral equation, which is obtained by applying the equations of elasticity to the problem. A computational program has been written to obtain the theoretical results. Stress intensity factor has been calculated for different values of crack length and loading condition. From the stress intensity factors, the stress distribution around the crack tip also has been determined theoretically. A relation between mode-I and mode-II stress intensity factors has been established for a specific range of crack length and loading condition. Stress intensity factor and the stress field can be easily determined by using this relationship. A finite element modeling of the problem also has been carried out in a finite element software, ANSYS and the theoretical results have been compared with the finite element results. The results were found in good agreement.