Effect of aspect ratio for FRP wrapped biaxially loaded circular columns

Abstract

Experimental investigation of column specimens with and without external Glass Fibre Reinforced Polymer (GFRP) wrapping was carried out in this paper. Parameters such as aspect ratios of 2 (170 mm x 340 mm), 2.94 (170 mm x 500 mm), 4.12 (170 mm x 700 mm), 6.47 (170 mm x 1100 mm) and M20 and M30 grade of concrete were taken as variables for this investigation. For one particular aspect ratio and grade of concrete, a total of 18 specimens were cast. Out of these, nine were unwrapped specimens and the other nine were wrapped with a GFRP sheet. Furthermore, a single group of nine specimens were subdivided into three subgroups based on eccentricity of loading. Thus, a total of 144 specimens were cast. The specimens were loaded axially and biaxially, until failure. The experimental results clearly demonstrated that composite wrapping could enhance the structural performance of the concrete columns under eccentric loading to some extent, while the enhancement was more significant for columns under concentric loading.