Prediction of Tensile Capacity of Bond Anchorages for FRP Tendons

Abstract

Past test data show that the bond stress distribution of bond anchorages is nonuniform along the bonded length and that the point of the peak bond strength shifts from the entry of the tendon to an inside point of the anchorage as the applied load increases. Based on these results, this paper analyzes the working mechanism of bond anchorages for fiber-reinforced polymer (FRP) tendons and presents a conceptual model to calculate the bond stress at the tendon-grout interface and the tensile capacity of bond anchorages for FRP tendons. Experimental and analytical results show that the geometry of FRP tendon and steel sleeve and the mechanical properties of filling grout are the relevant parameters in the development of tendon-grout interface stresses. The characteristic bond strength depends mainly on the properties of the bonding agent-cement grout, the geometry and surface conditions of the tendon, and the radial stiffness of the confining medium. A comparison of the calculated and experimental results showed good agreement.