Use and Care Manual

5.3 Compaction Terms
5.3.1 Cohesive soils: Clays and mixes have a particular particle size of less than .003” or .002”
and are typically classified as cohesive soils. This type of soil is primarily used for retaining
pond beds and mound fills. These soils are dense due to the strongly bound molecular
attraction. Cohesive soils and water will not mix easily, but only once the soils are moist it will
feel sticky.
5.3.2 Granular soils: These soils have particle sizes of .003” or greater, like sand. Water drains
easily through the soils particles of granular soils. The larger the particles, the larger the
equipment needed to achieve lower frequencies and higher compaction force. Plate
compactors are typically the best option for compacting granular soils - however, depending
on the vibration frequency and particle size, reversible plate compactors and double drum
rollers may be more appropriate for this type of work.
5.3.3 Mixed soils: Sometimes soils can be a mixture of both types, cohesive and granular.
Thus choosing the appropriate compaction equipment is more difficult. We recommend
testing your equipment to match the best machine to the desired job.
20