Cross hole sonic logging

Cross hole sonic logging is a foundation testing method employed by JF Strainstall to verify the structural integrity of drilled concrete piles and shafts.

With decades of experience, JFTS uses the latest SCXT3000 sonic logging system to test, view and store critical data on the structural soundness of the concrete.

JF Strainstall offers a high end analysis service which includes 2D and 3D tomography reporting for fast visualisation of foundation defects.

Cross hole sonic logging methodology

Cross hole sonic logging uses ultra-sonic transducers to measure the transit time of sound in concrete. The test is carried out in foundations where steel tubes have been installed during construction, normally to full depth.

Probes are lowered into the tubes and cables are then raised using the systems electronic logging winch. As the winch wheel turns, the emitter sends an ultra-sonic signal which travels between transducers in selected tubes to a receiver.

The signal is captured and stored as a time / amplitude trace for every 1 centimetre of the pile length. Traces are combined into one sonic profile or waterfall plot, and the first arrival time (FAT) can be used to determine the ultrasonic pulse velocity if the distance between the tubes is also measured.