Energy absorption of steel hollow tubes under bending

Abstract

This work describes an analytical study on steel circular hollow sections under pure bending moment in order to understand its collapse deformation and to predict the energy absorption mechanism. Different from experimental and numerical analyses, which require extensive resources, the yield line mechanism (YLM) analytical model utilised in this work could provide various useful insights such as the collapse response of steel hollow sections when failure is formed at localised plastic hinge points. This is when a section fails and the YLM of failure forms at its localised plastic hinge point. Initiating a geometrical model and determining the energy absorption by different hinge lines is a complex exercise. Therefore, a simplified equation to estimate the failure curve of steel hollow sections is proposed. After examining the collapse response of the steel hollow sections using a simplified YLM method, the energy absorption capacity of these sections is investigated by performing excessive parametric study and correlation. By using this simplified method, the energy absorption due to failure is investigated. It is concluded that, for sections with the same cross-section, the section with the lower slenderness ratio has a higher energy absorption capacity and is more desirable to use as an energy absorber in industry.