An Experimental Study on Flexural Property of Damaged Concrete Beams Reinforced with High Ductile Concrete

High ductile concrete (HDC) has positive ductility, bond property, and damage resistance feature. Therefore, it can be used to reinforce damaged concrete beams, which can not only improve the bearing capacity of the beams, but also prevent the further development of cracks. This paper used HDC for surface reinforcement, tested the flexural property of five earthquake-damaged concrete beams reinforced with HDC, and studied the bearing and deformation capacity of the earthquake-damaged concrete beams reinforced with HDC, as well as the internal damage of the concrete. The experimental results show that the bearing capacity and deformation capacity of the earthquake-damaged concrete beams reinforced with HDC are greatly improved. The bearing capacity of reinforced RCL1-RCL5 is increased by 86.1%, 75.7%, 56.0%, 84.4%, and 65.7%, respectively, and the corresponding load of the initial crack is increased by 36.4%, 86.6%, 64.3%, 28.9%, and 29.7%, respectively. By comparing the earthquake-damaged concrete beams reinforced with HDC before and after the failure, this paper finds that HDC has shown positive bond and damage resistance properties, and both the original concrete and HDC are subjected to forces and deform. According to the study on the flexural property of earthquake-damaged concrete beams reinforced with HDC, the calculation formula of the flexural capacity of the earthquake-damaged concrete beams reinforced with HDC is deduced, and the calculated results agree with the experimental ones.