Flexure of Reinforced Concrete Beams Externally Strengthened by Epoxy Bonded Steel Plates with Anchored Bolts

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Yos Sompornjaroensuk


An extension of the previous work on strengthening in flexure of reinforced concrete beams by external bonding of steel plates with epoxy-resin adhesive to the concrete tension face and providing additional mechanical anchorages at the ends and intermediate of steel plate is conducted and presented in the paper. A total of 14 beams having the same overall dimensions are cast-in-place using ready mixed concrete for the experiments. The internal steel reinforcement and steel plate quantities used are the same to that of the previous. The difference is only the concrete compressive strength. All of the beams have been tested until the beams failed under the four-point bending test. The objectives are thus to study the effects of concrete strength on load carrying capacity and deflection behavior of strengthened beams including the mode of failures. The parameters of interesting are involved with the steel plate thickness, type of internal reinforcing steel bars on beam sections, and position arrangement of mechanical anchorages. The cracking load, yielding load, debonding load, and ultimate load are determined experimentally and theoretically.

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