NON-LINEAR FE ANALYSIS OF SIMPLY SUPPORTED STEEL BEAMS WITH RC SLAB UNDER ELEVATED TEMPERATURES

Steel beams with reinforced concrete slab on steel decking provide an easy and economic system for floor construction since they negate the need for shuttering. On the other hand, steel is well known to have some disadvantages when subjected to elevated temperatures. The main reason is the decrease of its mechanical properties when subjected to elevated temperatures. The purpose of the current paper is to study the behavior of simply supported steel beams subjected to elevated temperatures. Both composite and non-composite beams are studied. The analysis is performed using nonlinear thermal and static analyses through finite element technique. A general purpose finite element program, Cosmos/M is used in the current work. The studied parameters include the beam dimensions, applied load, and exposure duration to elevated temperatures. The non-composite beams were found to behave better than composite beams when subjected to elevated temperatures. The beam section factor was found to have a large influence on the performance of the system. Residual stresses after cooling down the beams were observed to approach the yield stress of the material for non-composite beams. For composite beams, the residual stresses reach and exceed the yield stress of the material.