Patent ID: 8033163

Claim:
A dynamic cone penetrometer (“DCP”) for automated evaluation of soil compaction in a keyhole type opening, comprising: an elongated shaft having a first end and a second end, the shaft having a flange and a handle adjacent to the flange near the first end, the flange extending in a direction generally perpendicular to the elongated shaft; the second end of the elongated shaft comprising a tip; an anvil fixedly mounted to the elongated shaft between the first end and the second end; the second end of the shaft having graduation featuring one or more horizontal markings spaced apart in generally vertical alignment to one another; a drop weight slideably mounted to the elongated shaft such that the weight is moveable along the shaft between the flange and the anvil; and an adjustable collar adapted to fasten around the elongated shaft and being movable on the shaft between the anvil and tip, the collar having cooperative graduations of comparable dimension to the height of the tip and graduations near the second end of the elongated shaft, the cooperative graduations of the adjustable collar adapted to be visually read against an apparatus placed horizontally across the top of the keyhole opening.