Steel tubes cast into bored piles for crosshole sonic logging (CSL) integrity testing, conforming to ASTM D6760.
Sonic logging tubes are installed inside reinforcement cages and filled with water, allowing crosshole ultrasonic testing of the concrete after casting. They provide the access path for transmitter and receiver probes used to detect defects such as necking, soil inclusion and honeycombing.
An ultrasonic pulse is transmitted through the concrete between tubes filled with a coupling fluid. Changes in wave velocity and signal amplitude reveal anomalies in the pile shaft. Tube straightness and joint watertightness directly determine whether test data is valid.