Experimental Flexural Behavior of Composite Beam using Cold Formed Hollow Square Section

Abstract

Structural hollow sections have excellent properties for resisting static loads, with regard to buckling, bi-axial bending and torsion. Structural hollow sections are generally used for truss components, considering greater stiffness and lateral strength. A square hollow section truss has about two third of surface area of same size I section. Hollow section truss may have smaller members as a result of higher structural efficiency. Construction of composite beam commonly includes I section. This paper deals with comparison of commonly used hot rolled or welded I composite section with cold formed hollow RHS and SHS composite section with respect to flexure and shear. Flexural tests were conducted to evaluate the structural behavior of the proposed composite beams. Two different steel sections were used for this study with nominal concrete strength of 30 MPa. The composite beams were tested under concentrated two points loading. The test results were plotted and compared with analytical results. The mid span deflections and slip were recorded for both composite beams. Buckling modes for both composite beams were identified. comparisons have been carried out between predicted beam strength as provided by Eurocode -4 and experimental test results. Sectional properties are checked for cold formed hollow square section using EN 1993-1-3.