VELOCITY MEASUREMENT ON AN ASPHALT AND NONDESTRUCTIVE DETECTION OF PIPE UNDER THE ASPHALT

摘要

Asphalt concrete is well known as viscous elastic and high damping material. One of us developed new type wide band ultrasonic tester with active transducer and experimented on asphalt. This tester is valid to high damping and scattering materials. Ultrasonic longitudinal wave propagated through more 20cm long and average velocity is measured within +- 30 m/s over the asphalt model. We applied to nondestructive detection of buried pipe under asphalt.