Dynamic Cone Penetrometer
The Geotechnical Laboratory has a Dynamic Cone Penetrometer manufactured by Humboldt. The dynamic cone penetrometer (DCP), originally developed by George Sowers, uses a 15 lb steel mass falling 20″ to strike an anvil to penetrate a 1.5″ diameter 45° (vertex angle) cone that has been seated in the bottom of a hand-augered hole. The DCP can be used effectively in augered holes in nearly all types of soils to depths of 15 to 20 ft. (4.6 to 6.1m). Components are zinc-plated and cones are heat-treated. The cone can be replaced with a Drive Tube Assembly for collection of 3″ x 10″ (7.6 x 25.4 cm) tube samples from hand-augered holes.
This penetrometer is used to determine a penetration resistance relationship with the standard penetration resistance of soils. The Sower’s DCP has been used in post-earthquake field investigations and for foundation evaluations, but relies on soil-specific correlations to estimate various engineering soil properties.