Application of GFRP on preloaded retrofitted beam for enhancement in flexural strength

Application of glass fiber reinforced polymer sheet was carried out on seventeen small scaled beams. Out of seventeen beams two were control beams and fifteen were preloaded at 0%, 40% and 90% of control beam. The main experimental parameters include arrangement of GFRP sheet, preload level at the time of strengthening and numbers of layers of GFRP. Analytical investigation was also carried out by using finite element modeling arrangement of FRP was evaluated by using ductility and toughness criteria. The results were indicated that numbers and arrangement as well as preload level have more influence on the stiffness, toughness and ductility of the strengthened beam, both at post cracking and post yielding stage, than that on the yielding and flexural strength of strengthened beam.