Published Paper Details:

In recent years, further studies have resulted in improvements in the design standard and the concrete quality has been greatly improved. For all of concrete-filled steel tubes are being employed in more constructions especially bridges, multi-story, and high-rise buildings. Hollow steel sections also can provide reduced weight and surface area when compared to equivalent open sections. Concrete filled steel tube (CFST) is a composite section integrated from a steel tube or a steel hollow section (SHS) with concrete filling inside the hollow part of the steel section. The steel section could be hot-rolled section or cold-formed section. However, the steel section type, grade, manufacturing, and concrete characteristic cylinder strength together control the overall section capacity. Concrete filled steel tubes combine the advantages of ductility associated with Steel structures, with the stiffness of a concrete structural system. After several pieces of research, it has been known that load transferred from the steel tube to the concrete by bond and shear connectors if the bond between the steel column and concrete inside is not made full use of, the flexural bearing capacity of concrete-filled steel tube column may not be fully acted. In this paper, an extensive parametric study is introduced to show the effect of concrete in the hollow steel section among different parameters. Moment rotation curves are plotted for various studied parameters as bolt grade, bolt diameter, pre-tension force, and endplate thickness. The main object of this research is to highlight the concrete filling effect on the connection between steel I-beam to steel hollow section column and studying the connection behavior in each parameter with and without concrete.