Assessment of design guidelines for shear strengthening concrete beams with FRP

Extensive research has been undertaken in the last 15 years on strengthening reinforced concrete (RC) structures with externally bonded fibre reinforced polymer (FRP) composites. FRP composites may be used to enhance the flexural, shear and axial loading capacity of various concrete members or their ductility. The technique has also been increasingly used in practice worldwide. Consequently, many design guidelines have been independently developed by different organisations to meet the requirement for practical design. Shear strengthening of concrete beams is often an important part of a strengthening scheme but the behaviour of such strengthened beams is complex and less well understood. This paper presents a comparison of shear provisions in a number of widely available design guidelines with an experimental database collected from the literature. It reveals significant differences between them and scope for improvement.