Transport Research Laboratory (TRL) Dynamic Cone Penetromer (DCP) testing is a hand held percussive penetration test developed to evaluate the strength of future road or pavement developments.

It is a non-destructive testing instrument designed for the rapid measurement of the in-situ strength of existing flexible pavements constructed with unbound materials. 

The TRL DCP probe is designed to give a continuous reading of in-situ resistance down to a depth of 850mm (or deeper). The test takes only a few minutes in each location with numerous tests being achieved in each site visit, providing a very efficient method of obtaining information which would otherwise require the excavation of test pits.