Investigation into the effect of circumferential through-wall slits on a cantilevered pipe subjected to a transverse end load

Abstract

The main motive for carrying out the investigation is to explore the possibility of using slits to weaken the main legs of an offshore jacket structure as a means of creating a structural mechanism that facilitates safe and predictable toppling of offshore platforms. Cantilevered mild steel tubes containing through-wall circumferential slits are subjected to a transverse end load which causes the slit to open by hoop cracking. The effect of the slit geometry on the collapse characteristics of the tube is investigated experimentally and theoretically. A number of methods are used to predict the global load-deflection characteristics of the tube. These include a number of semiempirical methods based on the J integral and a numerical analysis utilizing the ABAQUS finite element code. The effective net section stress criterion is also used as a simple method of predicting the collapse load. This investigation has relevance to safety in chemical and nuclear plants.