Mode-II stress intensity factors for special-shaped cylindrical shells in torsion

Abstract

Special-shaped cylindrical shells in torsion are encountered in engineering applications, which will induce the Mode-II singular stress fields next to circumferential crack tips. The Mode-II stress intensity factor (SIF) represents the strength of these singular stress fields and is an important fracture parameter. The crack problems for the cylindrical shells are typical finite boundary value issues. It is very difficult to get the exact solutions by using the classical theory of elasticity. In present article, based on the concepts of the conservation law and the elementary strength theory, a hybrid methodology to determine the Mode-II SIFs for circumferential cracked special-shaped cylindrical shells in torsion is suggested. Due to the introduction of elementary mechanics, the corresponding errors are also inevitably carried into the Mode-II SIFs. However, the finite element analysis indicates that the error of the Mode-II SIFs calculated by present method is acceptable.