Soil stabilization — what is it?

Soil stabilization - what is it?

In-situ soil stabilization is a technological process that consists in grinding and mixing native or fertilized soil (for example, when constructing embankments) with a stabilizing material (cement, lime or hydraulic road binders GSD) while maintaining the optimal moisture content of the soil skeleton. It should be noted that if you are interested in fixing soils, we recommend visiting this site.

Soil stabilization machines are self-propelled recyclers or mounted soil stabilizers. Another method of stabilization is the introduction of a soil-binder mixture into stationary nodes. The finished mixture is transported to the construction site, where it is laid.

Strengthening the soil with cement

Soil stabilization with cement is a process that involves mixing soil with a cement slurry. The grains of the sandy-pulverized fraction are connected and together with cement form a supporting frame. Soil particles that are not bound by cement to the clay and pulverized fraction act as a shock absorber of external forces and contribute to stabilization.

The best soils for stabilization with cement are soils that are similar in properties to optimal mixtures, i.e., those in which the grain and granulometric composition of the soil corresponds to the appropriate proportions.

The amount of cement used for soil stabilization depends on the soil grain size, composition and requirements. Cement increases soil cohesion and at the same time reduces water absorption and plasticity.

There are five main types of soil stabilization cement:

  • Portland cement (CEM I);
  • multicomponent Portland cement (CEM II);
  • metallurgical cement (CEM III);
  • pozzolanic cement (CEM IV);
  • multicomponent cement (CEM V).

Soil stabilization with lime

Soil strengthening with lime is usually carried out on cohesive and very cohesive soils (loams). Quicklime is used in the presence of soil with a moisture content significantly exceeding the optimum moisture content. Dry slaked lime is suitable for moderately cohesive soils, hydraulic lime is suitable for weakly cohesive soils. In humus and peat soils, soil stabilization with cement is not performed.

When in contact with water, quicklime spontaneously hydrates and forms calcium hydroxide. The heat generated during this reaction immediately dries out the damp soil. In addition, lime dissolves clay particles and forms pozzolanic cement by combining calcium with silica and aluminum oxides present in clay soils.

By adding a certain amount of lime to soils suitable for lime stabilization, soil properties can be improved, i.e. improve the performance of lime-treated substructures. The result is stronger, stiffer and (by volume) lime-treated bases, sub-bases or base layers.