Sonic Log Casings are designed to be a drive-pipe for sonic log monitoring instruments. These logs are used to check the porosity, void-distribution and cementation quality of concrete structures, piles, diaphragm walls and foundation shafts.

The casing, which is realised in thermoplastic material, is lightweight and easy to handle on jobsite. During the installation procedure the casing has to be tied to the steel reinforcement of the structure by iron wire or plastic strips; following complete flowing and curing of cement, sonic monitoring can take place. In homogeneous concrete, sound velocity is constant, about 4000 m/s. It decreases rapidly if there are defects such as soil inclusions, cracks or segregations. Sonic logging is a continuous measurement of sound velocity between an emitting device and a receiving sensor (microphone), which are lowered down two tubes along the structure.