Overview of Soil Stabilization Methods in Road Construction

Abstract

Soil stabilization is the process of improving the shear strength parameters of soil and thus increasing its bearing capacity in road construction. It is required when the soil available for construction is not suitable to carry structural load. Generally, soils exhibit undesirable engineering properties unless they are treated to enhance their physical properties. Stabilization can increase the shear strength of a soil and control its shrink-swell properties, thereby improving the load bearing capacity of a sub-grade to support pavement and its foundations. Soil stabilization is used to reduce permeability and compressibility of the soil mass in earth structures and to increase its shear strength. Mixing additives into the reaction mechanism, positively affecting its strength, improving and maintaining the soil moisture content, achieve stabilization. Therefore, these soil stabilization processes are suggested for most construction systems and can be accomplished by several methods. All these methods fall into two broad categories, namely mechanical stabilization and chemical stabilization. Mechanical Stabilization is the process of improving the properties of the soil by changing its gradation; chemical stabilization is the process of adding a physico-synthetic substance to the soil which reacts with the clay particles to fill the voids so that less water is needed to maintain a stable mix and, finally, a stable framework.