Composite Jacketed Concrete under Uniaxial Compression—Verification of Simple Design Equations

Due to their high strength-to-weight and stiffness-to-weight ratios; corrosion- and fatigue-resistance; and overall durability, fiber reinforced composites are increasingly being considered for use in jackets around deteriorating and understrength concrete columns. For this new technology to achieve widespread acceptance, there is a need to develop a solid engineering base for the design and prediction of response of such retrofit and repair schemes. The purpose of this investigation was to develop experimental data, based on a variety of reinforcing fiber types, orientations and jacket thickness, and to develop and/or verify simple design equations to estimate the response of composite confined concrete. Experimental results indicate that composite jackets significantly enhance the strength and pseudoductility of concrete. The proposed expressions for ultimate strength and strain are seen to compare well with experimental data, and a phenomenological model for confinement based on the composite behavior of the confined system is presented. The results of the use of a number of predictive equations are compared with the experimental data.