Finite Element Investigation on the Behaviour of Open-Web Steel Beams Subjected to Fire

This paper presents a numerical investigation on the behaviour of open-web steel beams under high temperatures due to fire using finite elements simulations. The study includes parent beams without openings as well as castellated and cellular beams taking into account uniform and transient temperature rise, material and geometric non-linear behaviour. The input fire is based on the standard temperature-time curve ISO834. The thermal and mechanical analyses are performed using the temperature dependent material properties given by Eurocode3 part1-2 recommendations. The FE models are used to estimate the temperature at which the failure occurs under a fixed uniformly distributed mechanical load. The most commonly used types of web opening shapes are considered (hexagonal and circular) for simply supported beams. The study shows that the numbers of web-openings and cells as well as their shapes are of high importance for the behaviour of castellated steel beams under fire conditions. Results are related to temperature profiles in steel beam cross-sections, variation of displacements with respect to temperature change and critical temperatures

Finite Element Investigation on the Behaviour of Open-Web Steel Beams Subjected to Fire Keywords:

Open web beam , cellular beam , castellated beam , finite element , ISO834 fire , critical temperature