This paper presents the results of a recent study conducted to refine the designoriented stress-strain model originally proposed by Lam and Teng for FRP-confined concrete under axial compression. More accurate expressions for the ultimate axial strain and the compressive strength are proposed for use in this model. These new expressions are based on results from recent tests conducted by the authors' group under well-defined conditions and on results from a parametric study using an accurate

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... lysis-oriented stress-strain model for FRP-confined concrete. They allow the effects of confinement stiffness and the jacket strain capacity to be separately reflected and accounts for the effect of confinement stiffness explicitly instead of having it reflected only through the confinement ratio. The new expressions can be easily incorporated into Lam and Teng's model for more accurate predictions. Based on these new expressions, two modified versions of Lam and Teng's model are presented. The first version involves only the updating of the ultimate axial strain and compressive strength equations. The second version caters for stress-strain curves with a descending branch, which is not covered by the original model. This is the Pre-Published Version.