The heavy dynamic probe is a relatively portable and reliable ground investigation tool which is used to generate a vertical profile of soil stiffness and variability which can be linked empirically to design parameters such as Cohesion, Internal angle of friction and SPT-N value
The rig itself can be carried in a van and man handled over rough terrain into difficult or restricted access locations such as rear gardens and yards with little damage to softstanding or tarmac.
The DPH tests involves driving a series of 35mm dia. Rods and steel tip or cone into the ground by means of an automatic trip hammer. The number of blows taken for each 100mm advance are recorded as the N100 value. A histogram of N100 against depth is compiled.
The method can also be used for identifying the edges of quarries or infilled ground, locating rock head beneath alluvium or identifying mine shafts and before and after comparisons of ground improvement.