The Proving Ring Penetrometer is a gadget developed specifically to be used in the field for soil assessment. It is used especially in determination of the bearing capacity of subgrades and in measurement of compaction of the soil. Normally having a conical point with an angle of about 30 degrees, the penetrometer provides an effective means for determining the degree of penetration resistance of the soil and is also useful for the shallow seismic exploration.

This device consists of T – handle, proving ring of 100 kgf (1kN) with maximum load pointer and calibration chart. It also contains a 500 mm extension rod marked at 100 mm intervals and a detachable cone point with a flat top measuring 1 square inch, both of which are cadmium-plated to avoid any possibility of rust formation.

This device that is referred to as the Proving Ring Penetrometer enables the determination of the required values of the density of the compacted soil and its bearing capacity within the shortest time. It has a digital direct-read gauging system that dispenses with tedious calculations and affords accuracy right down to the 0. 1 psi accuracy. This penetrometer also has an additional 37. 25-inch rod, graduated at 6-inch intervals and comfortable aluminum handle to make it easier carrying the rod in the filed.

The advantage of using this tool is that it is effective as well as being multiple purposes. The Proving Ring Penetrometer is designed to enable users relate the results with compaction data and other typical tests. It is used mainly during field checks as it is a less time consuming method than laboratory tests.

To ensure that the penetrometer is kept in good working conditions then all the parts must be well cleaned and the instrument is usually re-zeroed often. By frequently checking the cone for wear, it will be possible to assess the best time to either replace the cone or have it recalibrated alongside the dial indicator, to guarantee accuracy in the long-run, therefore such a procedure will require extreme care whereby the operator directly handles the dial indicator during its calibration.