DAMAGE DETECTION OF CIVIL CONCRETE STRUCTURES BY LASER DOPPLER VIBROMETRY

摘要

Conventionally, the damage level of concrete structures is evaluated by impact echo inspection, in which the sound excited by hammer impact is subjectively judged by skilled experts. In order to rationalize the judgment and eliminate the dangerous inspection works in tunnels or bridges, application of remote measurement by Laser Doppler Vibrometer is proposed here. The relationship between impact echo and surface vibration of structures measured by Laser Doppler Vibrometer is established, and identification method of damage in concrete structures which is based on frequency domain analysis of measured surface vibration is proposed. These results indicate that Laser Doppler Vibrometry has high potential applicability to damage assessment of concrete structures.