Identification of Water Pipe Material Based on Stress Wave Propagation

A nondestructive evaluation apparatus for determining a material used in a below ground service line comprising:

• a probe with a wave measurement device therein, wherein each probe is configured for insertion into an area corresponding to a location of a service line;
• a vibratory shaker that generates a service line wave through an exposed portion of the service line;
• a wave measurement device that detects at least two substrate waves created by the service line wave passing through the service line and into a substrate;
• a data acquisition system that identifies a velocity of the service line wave using the detected at least two substrate waves;
• and
• a processor that compares the velocity of the service line wave to a known set of wave velocities corresponding to different service line materials and identifies a service line material in the service line by comparing the velocity of the service line wave with the known set of wave velocities corresponding to different service line materials.