Paper Title
Assessing the Use of Rectangular Concrete-filled Steel Tube Beams in Construction Fields

Abstract
Three important parameters of rectangular concrete-filled steel tube (CFST) beams, namely, weight, cost, and ultimate moment capacity, are investigated in this research to establish the validity of using this type of composite member in the modern construction projects. Finite element (FE) analysis with ABAQUS software was performed to implement the models of the CFST members. The validity of FE modeling was confirmed through a successful comparison with the experimental result for the CFST beam. The results confirmed that the in-filling of concrete delays the local buckling of hollow steel tube (HST) beams, which enhance their moment capacity approximately more than 70%, and the self-weight of these members increased approximately 2.5�4.0 times, whereas the cost increased by only 10%�15%. Moreover, the HST beams with high depth-to-thickness ratio and/or low yielding strength usually indicated better improvement of ultimate moment capacity when in-filled with concrete. Nonetheless, the use of high-compressive-strength of concrete does not significantly improve the capacity of the beams more than those in-filled with normal compressive strength. Keywords- Concrete-Filledsteel Tube, CFST Beam, Composite Structure, Finite Element Analysis.