Abstract :
[en] Soil cracking primarily results from the development of tensile stresses among soil particles, caused by the shrinkage of surface soil layers during desiccation. Climate change and global warming intensify cracking in soils with high plasticity, potentially leading to irreversible damage to infrastructure and both surface and subsurface structures. Additionally, soil cracking exacerbates desiccation in the unsaturated zone, contributing to land subsidence, a major global and national issue in Iran. During the desiccation process, the stress state in cracked soils constantly changes, altering stress distribution among particles. Therefore, understanding stress redistribution in the unsaturated zone is essential as a fundamental mechanism in desiccation-induced soil cracking. In this study, thermo-hydro-mechanical modeling was employed to simulate the impact of climate changes in Qom city on a cracked soil, to investigate the transition of stresses from compressive to tensile near the cracks. Governing equations for the problem, including water and gas flow in the soil, energy transfer, and soil-atmosphere interaction, were defined in the numerical model. The results indicated that the initial compressive stress distribution in cracked soil was heterogeneous, with different stress patterns at the ground surface and crack tips. As desiccation progressed, tensile stresses emerged at the surface, crack walls, and tips, potentially leading to the propagation of existing cracks in both width and depth, as well as the initiation of new surface cracks.
