Evaluation of aramid and carbon fibre reinforced polymer composite tendonsfor prestressed ground anchors

This paper presents the tension and bond properties of commercially availab le Aramid fibre reinforced polymer (AFRP) and carbon fibre reinforced polym er(CFRP) rods and their uplift and sustained loading behaviour as ground an chor tendons. Variables for the tests were tendon type and constituent, gro ut type, and bond or fixed anchor length. Test results indicated that the t ension properties of fibre reinforced polymer (FRP) rods were close to the reported data. The surface geometry of FRP rods and the properties of filli ng grouts influenced the pullout behaviour and bond strength of grouted FRP rods. CFRP Carbon Fiber Composite Cable and Leadline anchors had a higher uplift capacity but lower creep displacement than AFRP Arapree and Technora anchors. The tested CFRP monorod and FRP multirod anchors with a 1000 mm f ixed anchor length exhibited an acceptable uplift behaviour according to ex isting codes. Creep behaviour appeared to control the long-term uplift capa city of prestressed FRP ground anchors. The recommended working load for po st-tensioned FRP ground anchors is 0.40 f(pu) for AFRP rods and 0.50f(pu) f or CFRP rods, where f(pu) is the ultimate load or strength of the anchor te ndon.