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.