Creep Rupture of Fiber Reinforced Polymer Prestressing Tendons under Curvature

The long-term durability of FRP prestressing tendons in a harped configuration or in flexure under short radius bends has not been extensively investigated. Creep-rapture data for straight uniaxial tension testing may not be representative of the material behavior in a prestressing application requiring curvature of the tendon. The FRP response in a harped or bent configuration may be comprised due to a lack of ductility in the outer fibers of the tendon. Long-term creep-rapture experiments conducted on harped Carbon FRP tendons are reported. The tests are conducted in a bend test so outer fibers are stressed up to 88 percent of the uniaxial strength. All tests are conducted in air at nominal room temperature. This paper presents design information concerning the long-term performance of harped FRP tendons and coiled storage of FRP tendons.