The paper discusses the experimental research carried out at Sheffield University  by the author. The main aim of this paper is to study the structural behaviors of T-beams strengthened by glued steel plates anchored at the ends with L-shaped plates to prevent the premature debonding failure. Further, the relative performance of external plates is compared with equivalent internal reinforcement designed to achieve the same ultimate strength. Results are presented for 24 T-beams; the variables studied are concrete strength (20-50MPa), plate thickness (1.6-6mm) and double or single plate layers.
The results is discussed and demonstrated a reduction in bar strains, central deflections and crack widths was between "30% and 53%" at service load. The theoretical ultimate load of the composite section was achieved for beams with single and double plated and the maximum increase in strength is 41%. Tests results on beams with 25% to 72% of their main reinforcement replaced by steel plates show that at service load a reduction in bar strains, central deflections and crack widths are between "54% and 66%".