Dependency of thermal properties of clayey soils on salt concentration

用双探针式热脉冲DPHP技术，测量了含有不同粘土矿物、蒙脱石、高岭石和变色剂的土壤的热物性、导热系数、体积热容和热扩散率。所有土壤的导热系数和热扩散率均在0.05mol/L时下降，这可能是由于盐溶液改变了粘土矿物的排列所致。对于用其他浓度的氯化钠或氯化钙溶液润湿的土壤，热性质随着浓度的增加而降低。二维有限元模型显示，粘土矿物排列的变化阻碍了热流。

Thermal properties, thermal conductivity, volumetric heat capacity, and thermal diffusivity, were measured for soils containing different clay minerals, montmorillonite, kaolinite, and allophone, moistened with several concentrations of NaCl or CaCl2 solutions using a dual-probe heat-pulse, DPHP, technique. Thermal conductivity and thermal diffusivity for all soils moistened with NaCl solution showed a dip decrease at 0.05 mol/L. This may be resulted from altering arrangement of clay minerals due to salt solutions. For soils moistened with other concentrations of NaCl or CaCl2 solution, thermal properties decrease with increases in concentrations. A 2-D F.E.M. model revealed that alternation of clay mineral arrangement hindered heat flow.