Rehabilitation of poorly detailed RC structures using CFRP materials

In many reinforced concrete structures built in the 1970's and earlier, bottom beam reinforcement is not continuous and if a column support is lost due to terrorist attack or other unexpected action, the structure could be vulnerable to progressive collapse. The use of CFRP material may provide a solution for rehabilitating such structures. CFRP materials cannot develop full tensile capacity unless they are properly anchored to the reinforced concrete structure. The intent of this study is to find an effective method of anchoring CFRP material to a reinforced concrete beam so that the ultimate tensile strength of the CFRP is realized. In this study, ten reinforced concrete beams rehabilitated using different configurations of anchors were tested to assess the effectiveness of the anchors. Both CFRP anchors and CFRP U-wraps were investigated. The rehabilitated beams were loaded until failure of the CFRP material or anchor occurred. Different failure modes, strengths and deformation capacities of the rehabilitated beams were observed depending on the configurations of anchors. The maximum capacity was obtained using a combination of CFRP anchors and U-wraps.