Stresses in axially loaded cylinders with imperfections and cracks

The combined effects of imperfections in the form of the meridians and meridional cracks in axially loaded cylindrical shells are studied by means of a finite element programme capable of handling well defined, discrete cracks. Two basic mechanisms are shown to occur in shells in such a state: first, a redistribution of vertical load away from the cracked zone, and second, a redistribution from hoop membrane to meridional bending action. The mechanics of behaviour of shells with imperfections in the geometry and cracks are systematically studied by examining the effects of shell, imperfection, and crack characteristics, so that the dominant parameters controlling the linear elastic response of the shell can be isolated. Numerical experiments show that those parameters that influence the behaviour in an uncracked imperfect shell also influence the stresses accompanying cracking.