| High strength-to-weight ratio, corrosion free, good fatigue behavior, good shock absorption etc. enable CFRP (Carbon Fiber Reinforced Polymer/Plastics) composites to be potential replacement for steel tendons in bridge and structural engineering applications. The hardest obstacle for CFRP tendons to be widely used is regarding the methodology to anchor the CFRP tendons and to maintain the post-tensioning force during the service life of the structures. High ratios for tensile to compressive and to shear strength make it necessary to develop a new anchorage design concept for CFRP tendons.In this paper, a series of 2-million-times fatigue tests and analysis through finite element method have been done for the developing two new types of anchorage system for CFRP tendon. The first one is bond-type anchorage system that is characterized with RPC as bond medium. During tests and analysis, the influence of bond length and the slope of inner wall of the outer steel tube have been studied. The second one is conventional wedge-type anchorage system ameliorated before it has been used for CFRP tendons. During tests, the influence to anchor performance of anchor length, inner angle of barrel and the force on wedge have been studied.In this paper, fatigue theories and S-N curves have been reasearched based on many domestic and overseas experimental data ripely and lots of literatures. A S-N curve has been brought forward with the modified parameter partially, by which the life of anchorage systems can be forecasted to a certian extent on test conditions of this paper.Subsequently, the fatigue behavior of the Bond-type Anchorage system mentioned above has been analyzed through finite element program—ANSYS. The experimental results has validated the correctness of the analysis data.At last, this paper puts forward some advices and advertent problems to anchor methods, which will be more adapt to CFRP and develop the anchorage systems.
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