Non-Destructive Inspection of Concrete Structures Using an Electromagnetic Wave (Radar) Based on a Signal Propagation Model

Nondestructive inspection by the electromagnetic wave (Radar) conventionally presents shaded images on the magnitude variation of the amplitudes of reflected waves. Therefore, identification of cracks and cavities in concrete structures is marginally successful in the viewpoint of the reliability and the accuracy. This is mainly because the conventional method aims a qualitative diagnosis of the anomalies based on inspector's eyes. This paper thus proposes an effective inspection procedure which can identify the locations of cracks and cavities quantitatively in concrete structures (and also the thickness of the cavities). It is based on a signal propagation model (i.e., a stack model of reflected waves) and a pattern matching strategy. Results show that the proposed procedure enables an accurate and a reliable identification of cracks and cavities in the structure.