Research Of Reinforced Steel Beams Strengthened With Hybrid-anchored Steel Plate

In recent years, steel plates and high strength straps made of advanced materials, such as fiber-reinforced polymers, have been used increasingly in the reinforcement project of Civil Engineering. Traditionally the steel plate or high strength straps was adhered directly on the lower surface of the bending beam. However this kind of directly bonding reinforcement would extremely cause stiffness mutation and stress concentration on the end of the plate which would result in premature debonding failure. In order to avoid this kind of failure mode and improve the utilization rate of material strength, experimental studies had confirmed that external end-anchorage system have shown great power in reducing the interfacial stress and preventing the premature debonding failure in the end of the strap. The main work and results of this paper are summarized as follows:1. Using three stage to analysis the interface stress of the end-anchor steel plate reinforcement steel beam, which is based on the linear elastic fundamental assumption, and giving the interfacial normal stress and shear stress formula of hybrid-anchored reinforced method.2. Using ABAQUS to analysis the interfacial stress and compares with the analytical solution, the results have a good agreement between each other. The analytical prediction clearly indicates that applying an external anchor to the strap end significantly mitigates the stress concentration within the strap-end region.3. The stiffness of the external end-anchorage systems is the first put forward in this paper, and the solving formula of the external end-anchored system which relations to the axis force of the steel plate is giving in this paper. In addition, the relevant parameters of the stiffness of the external end-anchorage system are discussed.