Soil Stabilizers

Soil stabilizers act through binding soil particles together, improving water resistance and/or making compaction easier to perform.

Basic categorization of soil stabilizers is into manufactured products and waste products. Two most common manufactured soil stabilizers are lime and Portland cement, while waste or by-products used are fly ash and cement kiln dust (CKD).

Forms of lime used for soil stabilization are quicklime, hydrated lime and lime slurry. Lime as soil stabilizer has quite limited application, primarily as it is successful only in treatment of clay soils with certain particle size distribution and plasticity. Even very low rate of organic matter or sulphates, such as 1%, makes stabilization with lime more difficult. Application of quicklime results in large water consumption, which can be technical and/or financial problem. Hydrated lime is in form of fine particles, which imposes dust generation issues during application and afterwards if treated terrain is unpaved. Slurry lime is characteristic for slower application rates and requires extra equipment which imposes higher operational costs.

Cement also doesn’t have broad application in soil stabilization as it requires certain particle size distribution and it does not tolerate high presence of clay and any presence of organic material. It is not suitable for regions with large range of temperatures as cement treated terrains crack due to freeze/thaw cycles. Both cement and lime have energy demanding production. This means that applications of these soil stabilizers also have high carbon footprint.

Fly ash is a by-product from coal-burning power plant. Its effectiveness depends on type of coal burned and type of combustion process implemented. If it does not contain enough lime, activator has to be added. Fly ash contains heavy metals and other compounds which negatively affect environment when leach. Due to high water solubility, leaching of these compounds to surrounding media has been noted in the past.

Cement kiln dust is a by-product from cement production. CKD occurs in forms of various chemical contents, but for the purposes of soil stabilization, it has to contain certain concentration of lime. Performance of this soil binder is poor in regions with freeze-thaw cycles. Cement kiln dust must be applied carefully to prevent environmental contamination. The toxicity of CKD must be determined for every case separately. The same as with fly ash, stabilization of soil with CKD has caused and may continue to cause, contamination of nearby soils, surface water and ground water.

Regardless of physical characteristics and chemical content of soil, it usually needs to be stabilized prior to use as road base, construction base, parking lot, etc. Common soil binders partially fulfil soil stabilization requirements but with significant environmental impact. Global Road Technology made things easier by developing soil stabilizers which are environment-friendly and applicable to all types of soil. GRT products are even compatible with old asphalt material. Furthermore, application procedure is greatly simplified by using only a water truck, grader and roller, making terrain operable within a few hours of GRT’s products being applied. Environment-friendliness is confirmed by Environmental Resource Management (ERM). GRT suppressants have low carbon footprint, as well as all activities associated with them.

Applications of GRT soil stabilizers result in more robust, resilient and flexible roads and terrains than when treated with common soil stabilizers. They accommodate movement, moisture and temperature that would crack other surfaces and survive through extreme weather conditions.

For more information regarding Global Road Technology or soil stabilizers please contact GRT.