Experimental Research on Flexural Behavior of Load-Bearing Characteristics on Reinfoeced Concrete Beams Strengthened with near Surface Mounted Prestressed CFRP Tendons

In order to improve flexural behavior of concrete beams, the 7mm-diameter carbon fiber reinforced plastic (CFRP) tendons applied different levels of prestress were put in to 20×20mm grooves opened in the concrete surface of the tensile region in the concrete beams.Grooves were filled with building structural adhesive, when it solidified bending test of strengthened beams would carry out. Flexural behavior of nine RC beams strengthened with prestressed near surface mounted CFRP tendons applied different levels of prestress and one unstrengthened RC beam were studied. In these tests, bending stiffness and load-bearing characteristics of test specimens were studied. Experimental results show that the high-strength performance of CFRP have been made full use; the stiffness of strengthened beams risen notably, the maximal crack load increased by 303.17%, the maximal ultimate load increased by 237.92%.