Dynamic ReplacementTM improves the strength of saturated cohesive soils and soft organic soils, when dynamic compaction is not effective due to the high fines content of the in-situ soils.
Dynamic Replacement columns are formed by placing a blanket of aggregate over the site, and driving the aggregate into the soil by dropping a 15 to 30 ton pounder from heights ranging from 30 to 120 feet. Alternate filling of the Dynamic Replacement column and compaction of the material are performed until completion of Dynamic Replacement columns.
The ability to determine the strength and soil geotechnical properties of the large volume inclusions and the soil improvement between those inclusions has enhanced the application of dynamic replacement as a ground improvement system. Large diameter ( 8 to 12 feet) columns are driven to depth up to 25 feet and typically take the form of mushroom pillars.
