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This research paper deals with an experimental study of reinforced concrete beams in which the beams are strengthened in flexure by externally epoxy bonded carbon fiber-reinforced polymer (CFRP) plates. The objectives are to investigate flexural strength capacity and deflection response behavior of beams with two different types of reinforced beam cross section between single and double reinforcements. A total of 14 beam specimens with the same overall dimensions are cast-in-situ using ready mixed concrete for laboratory tests, which can be divided into two groups depending on steel reinforcement types. In each group of beams, the first four reinforced concrete beam specimens are imposed to be as the control beams that loaded by point loadings at the distance of one-third point of span length, and loaded at the distances of 1.5, 2.0, and 2.5 times of beam depth measured from two supports. The remaining three beam specimens are strengthened by CFRP plates and also loaded at 1.5, 2.0, and 2.5 times of beam depth measured from the supports in the same manner with control beams. The tested results have been prepared and given first for the load-deflection response. Analysis of obtained results are presented and discussed for cracking load, yielding load, debonding load, and ultimate load. Some results are compared with available theoretical calculated results.
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Copyright @2021 Engineering Transactions
Faculty of Engineering and Technology
Mahanakorn University of Technology
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