Characterization of a pultruded FRP sheet pile for waterfront retaining structures

This paper presents a series of experiments carried out to determine the characteristics of a pultruded fiber-reinforced polymer (FRP) sheet pile profile for waterfront retaining wall applications. The profile's flexural and shear stiffness were determined through a multiple-span test method, and the moment resistance was obtained by simulating the earth pressures using a uniformly distributed load. It was found that the load-carrying capacity was dominated by the buckling of the compressive flange and web. Water absorption tests were performed to assess the maximum percent absorption and the corresponding mechanical property change; a saturated pultruded FRP was shown to decrease tensile strength substantially, but this did not cause significant change in the longitudinal modulus of elasticity. Pultruded FRP exhibited excellent resistance to freeze-thaw cycling. The results of the creep tests predict that, over 30 years, the deflection creep of the sheet pile profile will exceed 70% of its static deflection.