Review of methods for predicting soil volume change induced by shrinkage

The shrinkage of soil induced by cyclic moisture variation from the post-compaction state needs to be addressed for understanding its long-term performance. The soil shrinkage curve is modeled to characterize the loss of moisture and the associated soil volume change from the initially saturated state to zero volume change phase. The volume change associated with gradual loss of moisture provides insight into the pore volume change, thus necessitating an accurate determination of soil volume. In this article, a detailed review of various measurement methods practiced to quantify the volume change of soil during the desiccation process in the laboratory is discussed. The procedure outlines, advantages, limitations, and the implication of results are discussed elaborately to understand their implications on shrinkage curve characterization. The absolute error of volume measurement by non-contact measurement method can be as low as 0.3% compared with direct measurement procedures. The study highlights the necessity to quantify the anisotropy in volumetric shrinkage and the advantage of using non-contact measurement methods. In particular, this review on the current state-of-the-art practices emphasizes digital image analysis as a cost-effective and reliable approach to quantify the shrinkage of fine grained soils, especially highly expansive clay.