Demolition engineering: Lateral load carrying capacity of weakened steel beams

摘要

This paper is aimed at assisting in the production of structural engineering techniques to ensure that structures can be both safely and efficiently demolished when they reach the end of their lifecycles, specifically for demolition by the technique of 'lateral pull-over'. This is done by considering a specific type of weakening technique that facilitates the collapse of a steel column through the application of a lateral load delivered by plant machinery. A test setup was developed and all tests were performed on standard IPE160 S355JR steel sections. Lateral failure loads of between 19.2 kN and 23.3 kN, with an average of 21.3 kN were recorded for the weakening technique investigated. Control tests on cantilevers showed that the failure load of the weakening technique was in the order of 17 times greater than the load initially expected due to a 'jamming action' on a central shim when lateral loads were applied. An Abaqus finite element model was implemented and calibrated which showed promising results that correlated to within 3.2% to the experimental data achieved from the test setup. The model is used to provide insight and explain the failure mechanism of the weakening technique studied. As the column sections are pulled out, they form a compression field and effectively jam against one another, which is overcome through localised yielding and the formation of plastic hinges.