2026 Volume 5 Issue 1 Pages 183-190
Tapping inspections are often used to inspect infrastructure structures such as bridges, tunnels, and underground cavities. However, with the declining birthrate and aging population, there is a shortage of skilled inspectors, and there is a need to make inspection work more efficient. Various methods have already been developed, but most of them require close contact with the inspection surface, and therefore have not led to improved work efficiency. Therefore, our laboratory has developed a noncontact acoustic inspection method that uses acoustic irradiation induced vibration and a laser Doppler vibrometer to enable inspections similar to tapping inspections, but from a distance and without contact. Verification experiments have already been conducted on test specimens and actual structures, demonstrating the effectiveness of this method. This paper introduces an overview of this method.
