Abstract

Reinforced concrete (RC) beams which are insufficient in terms of shear and flexural capacities are strengthened by various methods. Steel and fibre reinforced polymer (FRP) plate bonding methods are very widely used in strengthening of beams. Strengthening methods such as bonding steel and FRP plates have deficiencies as corrosion, fire and buckling. In this work, it is aimed strengthening of damaged RC beams using prefabricated RC rectangular and U cross-sectional plates. The rectangular cross-sectional plates were bonded to the bottom sides of the beams by rods and epoxy. The plates having U cross-section were bonded to the three sides of the beams. The strengthened beams were incrementally loaded up to maximum load capacities. The load carrying capacity of the beams increased 41% with the strengthening rectangular cross-sectional plates, however when the U cross-sectional plates were used, the capacity increased up to 76%. The experimental results were compared with the theoretical values. In addition, post-elastic strength enhancement and displacement ductility of beams were investigated. The advantages of this method do not require shuttering, concrete and steel workmanships in situ. Also, the application of this method is very easy and economic. For these reasons, this method should be preferred against other methods.

Key words: Prefabricated reinforced concrete (RC) plate, strengthening, experimental, theoretical, ductility.