Compaction using the CDC technique takes place from the surface of a site. The CDC machine consists of a hydraulic excavator base with a strengthened arm to which a compaction hammer is attached. A weight within the hammer generates vibration by the repeated drop onto a compaction foot that remains in contact with the ground. These vibrations bring the soil particles into a more densely packed structure. The increased density of the ground both improves its strength and increases the safety against liquefaction.
The CDC technique is cost-effective thanks to the high production rate of 1,500 to 10,000 m2 per 12 hours (depending upon compaction requirements and soil conditions). Influence can extend to a depth of approximately 9 metres. The very high compaction levels in the upper 4 to 6 metres make this technique ideal for land reclamation projects or in general in sandy soils. CDC uses “real-time monitoring” during the compaction process, which means that the compaction pattern, number of strokes and the foot diameter can be quickly adapted to local soil conditions.