Determination of optimum content of additive for stabilization of expansive soil considering its shrinkage, swelling, desiccation cracking, and shear strength response

Abstract

The current study proposes an approach for the determination of optimum additive content to stabilize the expansive soil for the construction of highway embankments by conducting an extensive experimental series of various tests such as one-dimensional swelling, in-laboratory desiccation cracking along with shrinkage, and unconfined compression. The conventional approach for determining the optimum additive content is based only on the increase in unconfined compressive (UC) strength. However, this approach is not suitable for expansive soils for which the major issues of concern are swelling, shrinkage, and desiccation cracking rather than UC strength only. The proposed approach determines the optimum content of the chosen additive based on the major issues of expansive soil (swelling, shrinkage, desiccation cracking) without compromising the shear strength (UC strength). Fly ash and lime were used for the stabilization of expansive soil in different percentages and the optimum content of each additive was determined using both approaches (conventional and proposed approach). The experimental results exhibited that the proposed approach for the determination of additive content gives a holistic solution for the stabilization of expansive soils covering all the issues, unlike the conventional approach.