Compressive behavior and analysis-oriented model of FRP-confined engineered cementitious composite columns

Abstract

A total of 18 specimens of fiber-reinforced polymer (FRP) confined engineered cementitious composite (ECC) were tested under axial compression in this study. Both monotonic loading and cyclic loading were considered. Effects of different FRP materials, glass FRP (GFRP) tube and carbon FRP (CFRP) jacket, as well as different FRP thicknesses were investigated. All the specimens exhibited the typical strain hardening behavior, indicating the effective enhancement of compressive strength and strain of ECC under FRP confinement. Failure modes, stress–strain behavior and dilation behavior were presented and analyzed. The FRP-confined ECC showed large ultimate axial strains, demonstrating the superior deformability and ductility performance. Design equations were developed to predict the ultimate compressive strength and strain. Based on the test results obtained from this study and other test results collected in the literature, an analysis-oriented model was proposed to predict the overall compressive stress–strain behavior of FRP-confined ECC columns.