Achieving Improvement with Dynamic Replacement 
Stone Columns – Impact Crater Depth -Capacity 

F. H. van der Merwe and C. Purchase 2017.

Proceedings of the 9th YGE Conference, Durban.

Dynamic replacement penetration tests, with both the Dynamic Compaction (DC) and Rapid Impact Compaction (RIC) methods, have been carried out on three sites in South Africa on variable ground profiles. Quality assurance is normally done by means of plate load tests on selected stone columns and a limit is typically placed on the acceptable deformation modulus, for the Engineer to approve works. The results from the penetration tests are presented, with a comparison of the achieved deformation moduli. 




Plate Load Testing (PLT)

Dynamic Replacement

Dynamic Compaction- and Rapid Impact compaction- replacement techniques are often used to improve the bearing and settlement/stiffness characteristics below structures or to choke cavities in dolomitic profiles. If used below a structure or fill, the stone columns are normally designed as a piled raft and capped with a high strength geotextile and a load transfer granular raft. 

Key Words: 

Ground improvement, Experimental analysis, Dynamic Replacement Stone columns, Penetration Testing, Plate load test