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The development of a wedge-type anchorage system for fibre reinforced polymer (FRP) tendons, as part of an overall corrosion-free post-tensioning system, is outlined in this paper. A stainless steel anchor is described, and results from numerical models and load tests to evaluate its behaviour under loads from anchor set, as well as static and repeated tendon tension, are presented. An alternative wedge-type anchorage system made from ultra-high performance concrete is also described. It is shown that, although significant progress has been made in development of the anchorage, further work is required to make it more robust.Key words: FRP tendons, post-tensioning, anchorage, corrosion-free, mathematical models, load tests, concrete.

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Advancement in material science has enabled the engineers to enhance the strength and long-term behavior of concrete structures. The conventional approach is to use steel for prestressed bridge girders. Despite having good ductility and strength, beams prestressed with steel are susceptible to corrosion when subjected to environmental exposure. The corrosion of the prestressing steel reduces load carrying capacity of the prestressed member and result in catastrophic failures. In the last decades, more durable composite materials such as Aramid Fiber Reinforced Polymer (AFRP), Glass Fiber Reinforced Polymer (GFRP) and Carbon Fiber Reinforced Polymer (CFRP) have been implemented in concrete structures as a solution to this problem. Among these materials, CFRP stands out as a primary prestressing reinforcement, which has the potential to replace steel and provide corrosion free prestressed bridge girders. Despite its promise, prestressing CFRP has not frequently been used for bridge construction worldwide. The major contributing factor to the lack of advancement of this promising technology in the United States (U.S.) is the lack of comprehensive design specifications. Apart from a limited number of guides, manuals, and commentaries, there is currently no standard or comprehensive design guideline available to bridge engineers in the U.S. for the design of concrete structures prestressed with CFRP systems. The main goal is to develop design guidelines in AASHTO-LRFD format for concrete bridge girders with prestressing CFRP materials. The guidelines are intended to address the limitation in current AASHTO-LRFD Bridge Design Specifications which is applicable for prestressed bridge girders with steel strands. To accomplish this goal, some of the critical parameters that affect the design and long-term behavior of prestressed concrete bridge girders with prestressing CFRP systems are identified and included in the research work. This paper presents preliminary results of an experimental study that is part of a National Highway Co-operative Highway Research Program (NCHRP) project.

Abstract. Advancement in material science has enabled the engineers to enhance the behavior of concrete structures. The conventional approach is to use steel for prestressed bridge girders. Despite having good ductility and strength, beams prestressed with steel are susceptible to corrosion when subjected to environmental exposure. The corrosio the prestressed member and result in catastrophic failures. In the last materials such as Aramid Fiber Reinforced Polymer (AFRP), Glass Fiber Reinforced Carbon Fiber Reinforced Polymer problem. Among these materials, CFRP stands out as a primary prestressing reinforcement, which has the potential to replace steel and provid CFRP has not frequently been used lack of advancement of this promising technology in the design specifications. Apart from a limited number of guides, manuals, and commentaries, there is currently no standard or comprehensive design guideline available to bridge engineers in the U.S. for the design of concret structures prestressed with CFRP systems. The main goal is to develop design guideline format for concrete bridge girders with prestressing CFRP materials. The guidelines are intended to address limitation in current AASHTO girders with steel strands. To accomplish this goal long-term behavior of prestressed concrete bridge girders with prestressing included in the research work. National Highway Co-operative Highway Research Program (NCHRP) project.