Application of infrared thermography technique for evaluation of cracks in concrete structures

Abstract

In this paper, a method to evaluate the crack size in concrete structures by infrared thermography was investigated. This method is based on the relation between the crack depth or width and thermal distribution at the surface of concrete. In the beginning, the influence of crack depth and width to thermal distribution was examined. Next, the influence of the distance between cracks and heater to thermal distribution was investigated. Moreover, the efficacy of this method was confirmed by the experimental result of flexural cracks in a reinforced concrete beam. From these results, it was clarified that the thermal distribution measured at the surface of concrete by infrared thermography was effective to evaluate the crack size in concrete structures.