Comprehensive analysis of thermo-mechanical responses in collapsible soil under varied water content conditions

Abstract In this research, the effect of both temperature gradients and varied water content on heat transfer in collapsible soil is investigated. The study based on one-dimensional laboratory setup, soil temperature distribution in proximity to a heat source, was examined across four distinct temperatures (ranging from 50 to 200 °C) under varying water content (0%, 10%, 15%, and 20%). Through steady-state conditions and extended measurements over days, data were collected to compare soil thermal conductivity at 10% water content using two different methods. The first method required some of soil characteristics, such as dry density and optimum water content, while the second method relied on heating parameters and supplied heating content. A robust agreement between thermal conductivity values obtained through these two methods was observed. Correlations from experimental data were analyzed to enrich understanding, and multivariate linear regression was employed to predict the thermal conductivity and resistivity of collapsible soils. Results indicated that the higher soil density, the increasing the thermal conductivity, whereas greater soil porosity exhibited the opposite trend. Elevated temperatures were found to enhance soil density, influencing the spatiotemporal distribution of heat within the soil. This research contributes valuable insights into the dynamic behavior of heat transfer in collapsible soil, emphasizing the complex interaction of temperature gradients and water content variations. The findings of this study can advance the development of efficient and sustainable geothermal systems in regions with collapsible soils, potentially enhancing the design and management of structures built on such soils, especially in arid and semi-arid areas.