On the Structural Behavior of Composite Beams Using Cold-formed Shapes

Cold-formed shapes have been increasingly employed in the construction of small multiple-floored buildings in Brazil, because wide flange shapes required to meet the demand are unavailable on the Brazilian market. Because existing codes fail to cover the design of composite beams constituted of cold-formed shapes, Brazilian design engineers have usually disregarded the contribution of the slab or have adopted improvised calculations that may to lead to unsafe results. The structural behavior of composite beams, constituted of cold-formed double channel shapes and connected to the concrete slab by means of shear connectors that were also cold-formed, was investigated experimentally. Simply supported beams were tested in which the degree of connection (number of connectors) and the type ofload (concentrated or distributed load) were varied. The results were then compared to those obtained through classic theoretical models of composite beam design, which supplied relevant conclusions for the design of these elements