This paper summarizes the experimental results from a comprehensive research program to study the fundamental stress-strain behavior of concrete confined by various types of fiber reinforced polymer (FRP) composite jackets. More than 200 concrete stub columns with 9 types of FRP composite jackets were tested under axial compression. The impact of different design parameters including plain concrete unconfined strength, types of composites as well as jacket thickness were considered in this study. The strength enhancement and ductility improvement of specimens confined with FRP composite jackets are discussed. In addition, a new stress-strain model to predict the behavior of axial members jacketed with FRP composites is presented. Comparisons between the analytical results using the proposed model and test results are also presented.
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