The technology of investigation of bored piles, precast piles and concrete bridge bearings by acoustic raying is intended for monitoring of pile properties: integrity, length, form and concrete strength class.

The essence of the method is mechanical excitement of the pile head, and assessment of the pile condition by comparing the measured properties and the echo-signal with the table of diagnostic characteristics for the various pile conditions. The technology was tested in 2002 in the construction of the laboratory building of St Petersburg State Mining University (Nalichnaya street), and on bridge bearings and the pile foundations of highways on the Ring Road and the Western High-Speed Diameter.