Response of Reinforced Concrete Box Girders Strengthened with composite Materials

The current research includes the results of a practical and numerical program to determine the best way to enhance the behavior of RC box beams where the practical program relied on casting and testing 15 samples under bending. The factors that were taken into account were the use of ferrocement laminate at the tensile side or in the form of a U-shape, the number of meshes, as well as its type (welded or expanded) and the use of composite materials (CFRP, GFR). For composite materials, the strengthening was carried out in different ways, where it was applied at the tensile side only and wrapping the composite material around the web like a U-shape along the total beam’s length or as strips with different sizes and spacing. The outcomes showed that the girders strengthened by 4 GFRP and 1 CFRP layers as a U-shaped have the highest service load and ultimate load.