Geophysics: Pile Integrity Testing (Sonic Echo/Impulse Response)
SE/IR or PIT testing provides a non-destructive method for various types of deep foundations, newly installed, or previously existing. This can be important for structural rehabilitation projects, or for Quality Control on new foundations.
SE/IR (PIT) testing involves transmitting seismic reflection waves inside of the concrete body, for structures with a length to diameter ratio of about 20:1. The reflection data will indicate the sonic impedance of the structure, which is related to structure narrowing, bulbing, or truncating. As such, the equipment can also be used to evaluate the foundation structure depth. The information obtained is communicated to the structural engineer to use for evaluation of the structure.
The SE/IR (PIT) testing equipment includes an instrumented hammer, a geophone, and an accelerometer. The equipment is lightweight and portable, but requires that a relatively smooth surface be prepared so as to have a clean hammer strike, and to have a secure mounting of the geophone and accelerometer to the top of the structure.