3 - Soil stabilization

Abstract

Soil stabilization is a very common process for almost all the road projects. Broadly, all types of soil stabilization can be classified into two groups, i.e. mechanical stabilization and chemical stabilization. In mechanical stabilization, the grading of a soil is changed by mixing it with other types of soils of different grades. By doing so, a compacted soil mass can be achieved. On the other hand, chemical stabilization is associated with the modification of soil properties by the addition of chemically active materials. In soil stabilization, it is very important to understand the material properties involved in the mixture and the outcome after mixing. Moreover, it is important to find out how the material is going to perform after stabilization. At the same time the effects of the process on the nearby structures and surrounding conditions need to be evaluated. Accordingly, decisions can be taken on the selection of materials and the corresponding doses. In addition to the selection of materials and the doses there are many other factors governing the effectiveness of this method, e.g. mixing and spreading, selection of roller, compaction layer thickness, compaction effort, sequence of operation, curing, environmental and climatic conditions, etc. In this chapter, the mechanical and different types of chemical stabilizations are discussed.