Rapid impact compaction (RIC) is a cost-effective technique used for shallow to intermediate ground densification. The energy delivered to the ground by RIC is of higher frequency and yields less vibration than its more robust counterpart dynamic compaction (DC).

As compared to DC, RIC is used at sites where shallower or lighter densification is required, at sites where space or access limitations would make mobilization of a large crane impractical, for small footprint projects, and when working near settlement- or vibration-sensitive structures.

Rapid impact compaction MENARD

Key Elements


Shallow to intermediate ground densification using energy waves from a hydraulic hammer weighing 7.7 to 9.9 tons that rapidly and repeatedly impacts the ground at 40 or more blows per minute.


The arrangement and careful calculation of the impact points of the pounders, as well as the other parameters of the treatment (energy, phasing, rest periods), are determined based on the characteristics of the soil and the results of a trial zone.


Reduce liquefaction and seismic-induced settlement, increase bearing capacity, reduce long-term settlement and collapse voids. Lower vibration levels with higher frequencies are less damaging to existing structures than the vibrations from dynamic compaction.

CMC techniques for soil

Rapid impact compaction (RIC) is performed by repeatedly driving a steel plate into the ground in a predetermined grid pattern.

Advantages of Rapid Impact Compaction Include:

  • Simple implementation – no materials are added to the ground
  • Performed with smaller excavator-mounted unit – a crane is not required
  • More protective of existing structures than dynamic compaction
  • Economical, particularly for small-footprint sites
  • Eliminates removal and replacement or traditional foundations such as piling
  • Very low carbon footprint as compared to other forms of ground improvement or traditional foundations
  • Does not generate spoil

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