Studying Flexural Behavior of Reinforced Concrete Beams Strengthened with Different Lengths of FRP Strips by Using NSM Technique

Abstract

This research includes practical results of study the behavior of the reinforced concrete beams strengthening by carbon fiber strips using near surface mounting (NSM) technique. The study is carried out on (8) concrete beams, the variables which considered are (the length of CFRP strips, no. of CFRP layers), this established by dividing the practical program into two groups, the first one includes (3) beams strengthened with variable carbon fiber strips length and one strip, Second group of this study includes (3) beams which strengthened with variable carbon fiber strips length and two strips, as well as two control beams . The results indicated that the carbon fibers had a noticeable effect in increasing the bearing capacity of the near surface mounting (NSM) strengthened technique reinforced beams, , the results indicated that strengthening the beams with carbon fibers and not along the length of the beam and in one layer did not contribute to increasing the beams strength, but when the number of layers was increased for the same length of fibers an increase in beam strength was noticed at a rate range (34%-55%).