Experimental comparison of cyclic behavior of RC columns strengthened with TRC and FRP

Abstract

Seven half-scale reinforced concrete (RC) columns with supporting beam were experimentally studied under combined axial and lateral cyclic loading. The specimens were categorized in two groups based on reinforcement ratios. Three specimens were strengthened with carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer (GFRP) sheets. Other specimens were strengthened using a high strength mortar reinforced with textile mesh (textile reinforced concrete (TRC)). Strengthening of specimens were carried out using a vertical layer and a horizontal layer of FRP sheet or two vertical and two horizontal layers of textile meshes for TRC specimens. Since the weight of each layer of textile mesh was half of the weight of FRP sheet, all the specimens had the same amount of strengthening fibers. Cyclic behavior, dissipated energy, ductility modification factor (m-factor), effective stiffness, effective yield strength, cracking patterns, and reinforcement yielding of all specimens were investigated and compared. The cyclic behavior of all strengthened specimens were improved, but the TRC specimens had a better performance. Also, with the same reinforcement ratio, the increase in dissipated energy, effective yield strength, and effective stiffness of the TRC specimens were more than the specimens strengthened with FRP sheets.