Abstract
Restoration of strength properties of crack repaired concrete specimen has been studied. Three-point bend tests were carried out on undamaged notched concrete specimens and damaged ones which crack repaired by epoxy resin, and restoration of the specimen was evaluated by means of fracture mechanics parameters such as the fracture energy G_F and the bending strength. The bending strength of repaired concrete specimen was proportional to the E-modulus of resin, and inversely proportional to the width of crack. The fracture energy (G_F) of repaired concrete specimens decreased with increasing the E-modulus of resin. The G_F value of repaired concrete were did not monotonously increase with increasing compressive strength of concrete, and had a tendency of decrease at low water cement ratio.