الفهرس | Only 14 pages are availabe for public view |
Abstract The heat transfer in collapsible soils is largely influenced by soil water content. This study investigated the coupled and mutual effects of temperature gradients and different water contents on heat transfer in collapsible soil. A one-dimensional lab-scale setup was constructed. The soil temperature distribution was investigated depending on how close the heating source is to the soil at four temperatures ranging from 50 °C to 200 °C and water content (Wc) conditions of 0%, 10%, 15%, and 20%. The experiments adopted typical characteristics of steady-state, with long measurement periods extending to days and all precautions taken to prevent heat leakage from occurring. The collected data was used to compare soil thermal conductivity as a function of elevated temperatures at 10% Wc measured by two different methods. One of the adopted methods required readily available soil characteristics such as dry density and optimum water content. The other methodology depends on the heating parameters and the delivered heating content. The measured thermal conductivity of the two methods corresponds to an acceptable range. The collapsed soil’s thermal conductivity and resistivity were predicted, considering correlations based on experimental results and the multivariate linear regression technique. The results showed that increasing soil density causes thermal conductivity values to clearly increase, while the opposite behavior was observed with higher soil porosity. On the other hand, it was found that elevated temperatures increase soil density and impact heat spatialtemporal distribution through the soil. The effects of temperature changes with different water contents on the reorganization of interlayer distance, macropores, micropores, and sorption forces related to the formation of collapsible soil micro-and macrostructures were investigated. |