Feasibility of Geo-Grid as confining Reinforcement in RC Columns: An Experimental Investigation

摘要

The experimental study presented focuses on the feasibility of geo-grid as a partial replacement of the conventional steel ties in reinforced concrete (RC) columns. Four different types of columns, consisting of a total of twenty-eight specimens, prepared using conventional steel and geo-grid as transverse reinforcement are investigated in the study. The performance of the specimens is evaluated using the parameters, viz. peak load, secant stiffness, ductility and energy dissipation by comparing the results with conventional specimens. Across the range of confining reinforcements used, for both the square as well as circular columns, the load–deflection curves were almost linear during initial phase of loading followed by non-linear stage and a descending branch indicative of the reduction in load-carrying capacity. Geo-grid confined specimens exhibited lesser spalling of concrete compared to control specimens. The peak strength and stiffness behavior of geo-grid confined columns are relatively better than the steel confined columns. However, the energy dissipation capacity and ductility reduced with a decrease in the amount of lateral steel ties. The geo-grid confined columns also exhibited a reduction in ductility and energy dissipation capacities relative to the control columns. An analytical model was developed to predict the strength of the geo-grid confined column specimens (both circular and square) of this investigation.