A Critical Review on Stabilisation of Expansive Soils with Compensating Materials

Expansive soils are mostly found in semi-arid and arid regions, and these soils suffer significant volume change when exposed to seasonal moisture fluctuations. Further, this volume change may cause extensive damages to the engineering structures and also the cost of damages increases every year. Practicing geotechnical engineers used different treatment methods to enhance the engineering performance of these soils. However, the placement of compensating materials in expansive soil deposits was found to be attractive for shallow stabilisation due to its construction feasibility and economic aspect. Extensive research has been carried out for the past 60 years for understanding the mechanisms of compensating materials in controlling the volume change of expansive soils. The engineering solutions to these soils consider various factors like the thickness of expansive soil, swell pressure, active zone profile, and properties of compensating material. This article reviews some of the essential aspects of the physical and engineering properties of different compensating materials and also the placement conditions followed in practice.