2D characterisation of cracking in lime-treated expansive soil during cyclic wetting-drying

The present experimental study investigates the effects of wetting-drying (W-D) cycles on desiccation cracking behaviour of compacted expansive soil treated with different dosages of lime. Large cylindrical specimens were subjected to a total of five W-D cycles under harsh climatic conditions to analyse their long-term performance with respect to desiccation cracking. Top surface images of the specimen were captured at the end of each W-D cycle using an image acquisition system and digital image analysis technique was employed to quantify various crack morphological parameters. The results of this study provide an assessment of the climate resiliency of lime-treated expansive soils used for the construction of pavement subgrades. The pattern of desiccation cracking drastically changed when the lime content was increased beyond 2%. The cracks formed were less in number but wider in specimens treated with up to 2% lime content compared to the very high number of cracks with relatively small widths in specimens treated with 4% or more lime. However, the specimens treated with 4% or above lime contents showed an overall better resistance towards the deteriorating effects of W-D cycles on desiccation cracking behaviour as the increase in various crack morphological parameters was nominal.