called Proving Ring Penetrometer
This is fork determining the bearing
capacity of sub grades or for compaction control. It also used for repidly determining
the penetration resistance of soils in shallow exploration work.
Consists of a study handle under which is fixed is a sensitive Proving Ring. An
extension piece is fixed to the bottom of the Proving Ring and carries a detachable
penetration con at its tip. Proving ring capacity 100kg (1KN) and 0.002mm dial
gauge provided indicates the penetration load applied. An optical viewer is provided
to facilitate reading the dial gauge by the operator. Simplified for single person
operation. A calibration chart is provided for the proving ring. Instrument is
complete in a wooden carrying case.
needles are used for quick evaluation of maximum soil density in the field. Standard
compaction curves showing moisture contents versus densities are drawn in laboratory
using standard compaction method and penetration of the proctor needles are correlated.
Proctor Needles are also known as Proctor Penetrometers.