Behavior of high-strength concrete beams strengthened with CFRP sheets in torsion

![CDATA[An experimental investigation of the strengthening of the torsional resistance of high-strength concrete beams using CFRP is conducted. A total of seven beams are tested. Three beams are designated as reference specimens and four beams are strengthened using CFRP wrapping of different configuration then tested. The variables considered in the experimental study include: different wrap configurations such as U-wrapping, full and strip wrapping, the effect of number of CFRP plies, the influence of anchors in U-wrapped test beams. The reference and the strengthened beams are subjected to pure torsional moment. The load, twist angle of the beams and strains at longitudinal, transverse re-bars and CFRP's are recorded to failure. In the study, increasing of the torsional capacity of the specimens is evaluated. The further study is the behavioral investigations included the varying of the cracking, yield and ultimate torsional capacity of the strengthened beams. Finally, experimental and different analytical results are compared together. The ultimate torsional strengths that are obtained by one of the analytical methods are in good agreement with the experimental results.]]