Behaviour of composite beams

ABSTRACT

                    Built-up I-sections have been extensively used whenever standard I-sections could not satisfy the moment carrying and shear capacities required. In these built up sections it has been common practice to use more steel in webs rather flanges. This results in uneconomical sections as steel is an expensive material. So introducing corrugated profile in web reduced the web instability and also the need for providing transverse stiffeners. But, even after in corrugated webs and lateral stiffeners, effects like lateral torsional buckling were observed. Thus measures other than providing conventional transverse stiffeners and corrugated webs were to be found. This paper deals with the investigation on Behaviour of encased cold formed built up I section with trapezoidally corrugated web and encased cold formed built up I section with plane web, under two point loading by varying H/T ratio of the beam specimen. The experimental results of encased trapezoidally corrugated web and that of plane web are compared and the behaviour and failure modes are discussed. Encasing the corrugated web of steel beam with concrete could improve the resistance to transverse deflections.