There are three broad types of soil stabilization: biological, physical and chemical.

Biological soil stabilization is achieved through afforestation or planting, and its main purpose is erosion control. This method is suitable for terrains exposed to water and wind influences which are not meant for building. However, initially planting has to be supported by other types of soil stabilization from the moment seeds or seedlings are planted till the moment the plants become strong. Otherwise, along with surface layer, seeds or young plants would be carried away by water flow or wind.

Physical types of soil stabilization include two different stabilization systems, one is drainage and another one is compaction. Drainage is beneficial as it removes excessive water from soil. Water makes soil more plastic and thus prone to deformation occurrence. Excessive water in soil can also cause erosion. Drainage system consists of set of pipes, canals and/or pumps, which makes it quite expensive to build. Compaction makes soil denser and thus less compressible and more water resistant, but for most of soils this method alone is not sufficient. It is usually additional measure to chemical stabilization.

Chemical types of soil stabilization are achieved through application of various substances which act as compaction aids, water repellents and/or binders. The most effective stabilizer is, of course, one that has all three possible characteristics. These substances are usually diluted with water and sprayed over soil which can be followed by mixing and compaction.

  • Cement is the oldest and still very common soil binder. However, cement application has many limitations. It is not compatible with soils with high amount of clay. On the other side certain concentration of clay is necessary for the method to be successful. Any presence of organic material is not allowed. Application process is quite complicated. High control of water content has to be performed, as well as demanding procedure for determination of right time for compaction. If viewed from economic and environmental aspect, cement production is extremely energy demanding.
  • Among chemical types of soil stabilization lime application is also very common. Lime compounds mostly used are calcium hydroxide Ca(OH)2 and dolomite Ca(OH)2+MgO. Lime is produced through a very energy demanding process and with high carbon dioxide emissions. Clayey materials are most suitable for lime stabilization, if they have PI values lower than 10. Pozzolanic reaction occurs in some clays, resulting in the formation of cementing agents that increase the strength of soil. It is not good stabilizer for silts, granular materials and soils with sulphate contents greater than 0.3 percent. If the treated material is not protected from runoff, some lime could be washed into the surrounding environment and have an impact by raising the pH.
  • Fly ash is another popular chemical stabilizer. It is a by-product of coal fired electric power generation facilities. It is among types of soil stabilization suitable for coarse grained particles with little or no fines. Soil to be stabilized should have low moisture content. After proper amount of fly ash added, an activator is usually used to intensify pozzolanic reaction in the mixture. The activator is lime or Portland cement in rate 20 to 30 % of fly ash.  Fly ash contains heavy metals and other harmful compounds which leach easily into soil and water bodies.
Global Road Technology has solutions for all types of soil stabilization issues:
  • Erosion control measure which enables planting can be achieved by application of GRT-Enviro Soil Binder. It is an organic conditioner which can be added to irrigation water to reduce soil erosion by agglomerating fine particles that would otherwise be carried away by surface water runoff. GRT-Enviro Soil Binder improves germination rate through creating optimal soil porosity and through retaining water, nutrients and plant protecting substances for longer periods.
  • Various construction terrains stabilization is achievable through use of GRT7000. It acts as a high performing stabilization agent as well as polymer sealant. When it comes to soil stabilization it is suitable for stabilizing subgrade, sub base and base of haul roads, side tracks, car parks, construction or military camps, container hardstands, railroad yards, and temporary landing areas.

GRT products applications are among types of soil stabilization applicable to all kinds of soils under various harsh climate conditions. They are independently verified as environmentally sustainable, manufactured to ISO9001 standards and have been comprehensively reviewed by leading independent testing institutions and major companies worldwide.

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