Lateral-torsional Buckling of Beams with Corrugated Webs Subjected to Fire

Abstract

The use of beams with corrugated webs (WCB) has been increasing considerably during the last years due to the high load-carrying capacity in relation to the material usage. The major asset of this structural solution lies in taking advantage of the increase of rigidity provided by the web corrugation leading to better resistance against local buckling and improved shear capacity resulting in higher load bearing capacity combined with significant weight reduction when compared with beams with flat webs. Despite known benefits of WCB, their behaviour, especially in fire situation, still lacks simplified formulae to enable the designers to exploit better this structural system. Focusing on this aspect, this study aims to develop simplified methods to predict the load bearing capacity, based on numerical simulations with the finite element method, overcoming the limitations encountered in adapting existing design methods of Eurocode 3 to the fire situation. A proposal is developed in this work which presents a new design philosophy for the fire situation closer to the principles of other structural systems while, at the same time, deliver more accurate solutions for the engineers in practice to use.