A State-of-the-Art Review on Axial Compressive Behavior of Concrete-Filled Steel Tubes Incorporating Steel Fiber and GFRP Jacketing

Several types of fibers have enhanced the structural response of reinforced concrete-filled steel tubes (CFSTs). This article presents a state-of-the-art review of studies done on the axial compressive behavior of steel and glass fiber-reinforced CFSTs. The aim of using fibers is to improve the response of the CFSTs. This research indicates the findings of experimental programs and analytical evaluations of the effects of the fiber incorporation on the behavior of the CFSTs. The results of this research work demonstrate that steel fibers (SFs) have enough evident improving effects on the failure mode and load-carrying capacity of the CFSTs. The SFs greatly increase the ductility of the CFSTs. To enhance the compressive strength and ductility of the CFSTs, adding the SFs by 1% to the concrete mix is more effective than adding by 1.5%. The use of the SFs mixed with expansion agent considerably increases the yield and ultimate loads of the CFSTs. More glass fiber-reinforced polymer (GFRP) sheets reduce buckling and develop the compressive strength of the CFSTs. The implementation of the GFRP jackets not only enhances the load-carrying capacity of the CFSTs, but also increases their ductility. The GFRP reinforcement techniques for the CFSTs are also effective in improving their structural stiffness and energy absorption capacity.