Analysis of desiccation cracking in high plasticity compacted clay using DIA and DIC

Clay-rich soils are often used for constructing various compacted geotechnical structures. However, prolonged exposure to high temperatures makes them prone to desiccation cracking, compromising their structural integrity. This study investigated the desiccation crack formation in high plasticity compacted clay under controlled drying. An automated image acquisition system was used to monitor crack development. Digital Image Analysis (DIA) and Digital Image Correlation (DIC) were utilized to quantify crack morphology and strain localization. DIA results showed that crack area increased steadily after reaching a critical water content, followed by a decline due to the soil’s self-healing property. The crack network stabilized once the final critical water content was reached. DIC analysis revealed that cracks originated at high tensile strain zones. Crack propagation modes including opening, sliding, and mixed modes were observed. A wide primary crack subdivided the surface into two clods, each with a distinct shrinkage center, indicating low tessellation tendency.