Detection of reinforced concrete crack using Mechano-Luminescence paint

As a nonuniform and unisotropic material with a relatively low tensile strength in spite of high compression strength, a concrete material is vulnerable to bending and tension. Due to the mechanical properties of the current reinforced concrete structures, it is hard for concrete materials to avoid the damages caused by cracks. Although cracks are the easiest things to detect and the most effectively repairable things due to their characteristics, it is very hard to measure them efficiently. In this research, the author measured cracks by visualizing them through mechano- luminescence(ML) paint. By applying ML paint on the surface of the specimen and using the 3-point bending test, the author conducted a quantitative evaluation on the mechanical properties of cracks such as the cracking aspect and length of reinforced concrete. Through the results of this research, the author confirmed the crack propagation speed by section and the mechanical correlation such as between loads and cracks and between deflection and cracks, which means this research was quite successful in analyzing the characteristics of cracks.