Soil stabilization is the process of altering properties of soil by changing the gradation through mixing with other oils or chemicals to improve strength and durability. Mechanical stabilization and chemical stabilization are the main two methods employed in stabilization.
Chemical processes such as mixing with cement, fly ash, lime, lime byproducts and blends of any one of these materials can be used to alter soil properties such as strength, compressibility, hydraulic conductivity, swelling potential and volume change properties.
The additives are combined with the help of machines. The method used depends on the location and availability of the machine. There are many types of additives used for chemical stabilization. But the selection of additive is based on the type of soil. A single additive act differently with different type of soils.
Cement stabilization offers better strength and improve soil quality. Normally Portland cement is used for this purpose. Stabilization using lime creates long-lasting changes in soil properties. Lime reacts with medium, moderately fine and fine-grained soils to produce decreased plasticity, increased workability, reduced swelling, and increased strength.
To enhance the effectiveness of cement, lime, fly ash stabilization or a combination of the three are used in required proportion. Fly ash is the byproduct of combustion of coal and contains Silicon and Aluminum and is mainly used as a filler product to reduce voids. The silicate aluminates-amide system is widely used for strength improvement and water cut-off as this system can be used in acidic soils as well.