STRUCTURAL PERFORMANCE OF HIGH STRENGTH LIGHT WEIGHT CONCRETE FILLED STEEL TUBE COLUMN UNDER AXIAL LOADING

High rise structures constructed with the lightweight high strength concrete filled steel tube (LWCFST) column has many advantages as compared to the regular steel or the reinforced concrete column. One of the main advantages of concrete filled steel tube (CFT) is the interaction between the steel tube and concrete, since the local buckling of the steel tube is delayed by the restraint of the concrete, and the strength of concrete is increased by the confining effect of the steel tube. This paper comprises the structural behavior of lightweight CFST column under axial loading and research findings about modulus of elasticity, bond stress capacity, comparison of theoretical and experimental load carrying capacity of CFST, and fire effect. Steel tubes are compared for different lengths, cross sections and constant thickness. By using Sintagg Light weight aggregate, high strength structural light weight concrete of M30 grade was developed which reduced dead load of structural column up to 25.30% as compared to normal concrete. Analytical values for squash load were calculated and found much less than experimental values showed the reserve strength in the columns, designed as per code specified formulae as per codes (AIJ, ASCI, EC-4 and BS-5).