Limit loading of cylindrical shells subjected to local circumferential bending moments

Abstract

Experiments have been carried out on twelve mild steel cylindrical shells each of which had a rigid radial square bar attached at its mid length. Strain and deformation patterns in the shell were measured when a hoop bending moment was applied to it through the attachment. Though some elastic stress distributions were obtained, the observations were mainly concerned with plastic deformations, the determination of plastic limit moments and the onset of instability. Measured deformation patterns were used to suggest a collapse mechanism from which a theoretical upper bound for the plastic limit moment was determined. Theoretical and experimental limit moments were compared for all specimens which had radius thickness ratios varying between 13·75 and 67·5, and attachment half width/cylinder radius ratios varying between 1 2·5 and 1 10·25 .