Effects of water content and salinity on the porosity structure and resistivity of loess soil sintered at 1000 °C

The spontaneous combustion of coal in oxygen environment changes the physical and mechanical properties and pore structure of rock and soil. In north of Shaanxi, the Quaternary loess is widely deposited on coal seam. In order to explore the influence of different factors on the change of loess properties after coal fire baking, loess samples with different initial water contents and salt contents were selected for high-temperature sintering. The effects of water content and salinity on the porosity and resistivity of loess after high-temperature baking were analyzed by basic physical property test, resistivity test and nuclear magnetic resonance test. The results show that, under the influence of coal fire, the porosity and main pore size increased with water content or salinity. With the increase of porosity, the resistivity first decreases and then increases. This paper systematically studies the influence of high temperature on the physical properties of loess under different conditions, which provides a reference for studying the effect of coal fire on loess in north of Shaanxi. © 2021, Saudi Society for Geosciences.