Soil Compaction

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Soil Compaction


the artificial alteration of soil properties for construction purposes without effecting a radical change in the soil’s physical or chemical state. Soil compaction consists in the reciprocal shifting of soil particles, as a result of which the number of contacts between particles per unit volume is increased; the increase is due to the redistribution of particles and to the penetration of smaller particles into the interstices between larger ones under the action of mechanical forces applied to the soil.

Soil compaction is used mainly to ensure prescribed soil density and thus to decrease the magnitude and unevenness of subsequent settling of beddings and earthworks. Soil compaction results in increased soil stability and decreased compressibility and filtering capacity. When water-saturated soils are compacted, water is squeezed through the interparticle pore space. The degree of soil compaction is measured by the density of the soil, that is, by the ratio of volume to weight of the soil with all moisture removed. Soil is conventionally termed compacted when this ratio is no less than 1.6 tons per m3.

Soil compaction is widely practiced in the construction of hydraulic engineering structures, roads and highways, railroads, and earthworks associated with the preparation of ground for urban construction. The technique is also used in filling in foundation pits and trenches after foundations are laid and in laying underground communications lines and pipelines. Soil compaction is especially effective in preparing beddings under buildings and structures erected on soils with nonuniform compressibility—fill, ground subject to subsidence, and water-saturated soils.

Soil may be compacted on the surface or to some given depth. Road rollers, compactors, and vibration plates are used for surface compaction. Deep compaction can be achieved through the use of vertical sand drains and piles and by means of the Vibroflotation process. Surface compaction is performed when the soil moisture level is optimum; if the natural moisture level is less than optimum, the soil is moistened prior to compaction. Probing and other subsurface exploration methods may be used to monitor the quality of soil compaction. Soil samples may also be taken from the compacted layer in order to test stability and deformation and filtration properties. (See alsoSOIL STABILIZATION.)


Nekliudov, M. K. Spravochnoe posobie po mekhanizirovannomu uplotneniiu gruntov. Moscow, 1965.



1. The process of inducing a closer packing of the solid particles in freshly mixed concrete or mortar during placement by reducing the volume of voids, usually by vibration, centrifugation, tamping, or some combination of these actions.
2. A similar manipulation of other cementitious mixtures, soils, aggregate, or the like.
References in periodicals archive ?
Soil compaction was shown to have a negative effect on infiltration rates of soils in north central Florida.
The most common cause of soil compaction is vehicular traffic with heavy farm machinery on wet soils.
Soil compaction effects of forwarding and its relationship with 6- and 8-wheel drive machines.
Some researchers have theorized that these volume changes would act to alleviate soil compaction (16), but that does not appear to be the case at either of these two long-term compaction sites.
Yet, soil compaction from large, heavy mammal trampling under arid conditions of southern Nevada have not been documented.
It is concluded that the measurements of root roundness (R) and flattening (F) are consistent with microscopic observations and can be used to quantify root deformation under soil compaction.
Soil acidity, for example, had a large dataset of georeferenced and time-stamped sample values, which allowed accurate statements of resource condition and trend, whereas soil compaction had few empirical data but many anecdotal reports and a lot of modelled examples.
The soil compaction market size is the biggest, followed by asphalt.
Soil compaction is caused of excessive sensibility plants to drought, inadequate ventilation, reduce water absorption, efficiency of nutrient elements, non-uniform growth of plants, slow germination and system of bad shaped roots and finally it is caused of reducing crop [6].
Michelin[R]YieldBib[TM] is capable of operating in the field at air pressures as low as 8 psi, reducing soil compaction and improving traction in all conditions.
If soil conditions do dry sufficiently then the next few weeks provide a good opportunity to try to rectify any soil compaction damage.