Effect of Steel Confinement on Axially Loaded Short Concrete Columns

Abstract

This paper presents experimental investigations of Reinforced Concrete columns strengthened with steel strips and steel jacket under axial compression loading. Total of six specimens were prepared in the laboratory, out of which; 1) two columns were unconfined columns, 2) two columns were strengthened with steel strips and 3) remaining two columns were strengthened with a steel jacket. All specimens were subjected to axial compression loading in increment until the failure of specimens using UTM at NUST. It was concluded after the experimental work that the steel strips enhanced axial load carrying capacity by a factor up to 1.54 times and steel jacketing enhanced the capacity by a factor of 2.38. It has also been observed that the steel confinement increased the cracking load by a factor up to 1.5 to 2.66 for strips and jacketing respectively. The failure occurred due to the crushing of concrete and buckling of steel strips and jacket between the fasteners. The steel strips and jackets are economical and feasible options for confining the concrete to increase its axial load carrying capacity.