For more than 20 years the Pile Integrity Tester – PIT – has been the go-to instrument for low strain integrity testing of deep foundations. In its simplest configuration, PIT performs pulse echo tests and consists of a main unit, one accelerometer and one hand held hammer. The hammer is used to impact the top of the foundation, producing a wave that propagates down the shaft and reflects back up. The reflected waves are received by an accelerometer which is attached (typically with wax) to the pile top. The main unit provides the testing professional with a velocity as a function of time log that may reveal a compromised foundation element. Some PIT models enable tests where two accelerometers are used, or where the hand held hammer is instrumented with an accelerometer, for an alternate method of integrity analysis (transient response/frequency domain analysis).
A few years ago, Pile Dynamics, Inc (PDI) released the PIT-X, a very compact Pile Integrity Tester that weighs only 500 grams and has a wireless configuration option (no cables connecting accelerometers or instrumented hammers to the main unit).
PDI has now reengineered the traditional Pile Integrity Tester giving it a large and bright color screen, a lighter enclosure and a USB port for data transfer. This model is available with one (PIT-V) or two (PIT-FV) channels of data acquisition, both traditional (wired). The PIT-FV is most often supplied with one accelerometer (provides velocity data through integration) and one instrumented hammer (force data, hence the name PIT-FV), but may also be used with 2 accelerometers (some special technical applications require two acceleration inputs).
In addition to the PIT, PDI offers a full line of instruments for quality assurance of deep foundations. For more information visit www.pile.com/PIT.