Solutions of Stress Intensity Factors of Multiple Internal Axial Cracks in Hollow Cylinders

Abstract

This paper solved numerically the stress intensity factors of multiple internal axial cracks in hollow cylinders under internal pressure. Semi-elliptical shaped cracks are modelled using ANSYS finite element program and the stress intensity factors are calculated using interaction domain integral which is based on the J-integral. There are two important parameters are considered such as crack aspect ratio, a/t is 0.2, 0.4 and 0.75 and crack spacing distance, d/c is 0.4, 0.7 and 1.1. For multiple internal axial cracks under internal pressure, stress intensity factors along the crack front decreased when crack aspect ratio, a/t is increased. It is also revealed that the role of crack spacing on the stress intensity factor is insignificant especially for the shallow cracks (a/t < 0.4). However, for the crack having a/t = 0.75, increasing the distance of d/c capable to increase the SIFs due to interaction effect.