Response of thermal conductivity of loess after high temperature in northern Shaanxi burnt rock area, China

Environ Sci Pollut Res Int. 2023 Mar;30(12):33475-33484. doi: 10.1007/s11356-022-24533-0. Epub 2022 Dec 8.

Abstract

Spontaneous combustion of coal seams can produce a high temperature of about 800 ℃, which greatly changes the thermal conductivity of the overlying loess layer. The thermal conductivity of loess plays an important role in ecological restoration design and the calculation of roadbed and slope stability. In this study, loess in northern Shaanxi, China was taken as the research object to measure the mass-loss rate and heat conduction parameters of loess specimens after high temperature. The test results show that, between 23 and 900 °C, with temperature increasing, the mass-loss rate is reduced. And the heat conduction coefficient (λ), specific heat capacity (c), and thermal diffusion coefficient (α) decreased by 48.9%, 23.1%, and 35.6%. This is due to the air thermal resistance effect caused by the increase of pores and cracks in loess specimens after high temperature.

Keywords: Chromaticity; Heat conduction coefficient; Loess; Specific heat capacity; Thermal diffusion coefficient.

MeSH terms

  • China
  • Hot Temperature*
  • Temperature
  • Thermal Conductivity