The Dynamic Cone Penetrometer (DCP) is a portable tool for rapidly measuring the in-situ structural properties of unbound road pavement layers. It consists of an 8 kg weight dropping 575 mm onto a 20 mm diameter cone attached to a shaft, allowing penetration measurements up to approximately 850 mm deep. Readings are taken after a set number of blows, adjusted based on layer strength: 5–10 blows for strong granular bases, and 1–2 blows for weaker sub-base layers or sub grades. The test requires three operators—one to hold the device vertically, one to operate the hammer, and one to record results. It’s quick, taking only a few minutes, and efficiently identifies layer boundaries and thicknesses without excavation.