非饱和土热力学参数确定的探讨

研究非饱和土热力学的力学性质,必须建立能量守恒方程,表征能量的两个基本物理力学参数(体积比热系数和热传导系数)的确定是求解能量守恒方程的重要因素.对于不同颗粒组成的土体,对其干燥颗粒有效热力学参数进行了分析,对固体、液体和气体三相共存的热力学参数进行了研究,并对计算结果进行了对比分析,在此基础上,提出了较适合计算热传导系数的方法,并将此方法和体积平均法、自洽法及Hashin-Strikrnan方法进行了比较.经与试验结果对比表明:提出的方法能较好地描述非饱和土的热力学参数特性.

Investigation on determination of thermodynamical parameters of unsaturated soil

It is necessary to establish the energy conservation equation to research the thermodynamical properties of unsaturated soil; the determination of two representative parameters (volumetric specific parameter and thermal conductive parameter) of fundamental physico-mechanical parameters is a key factor to obtain the results of the energy conservation equation. The effective thermal conductive coefficients of dry soil grain are analyzed for different composition geomaterials; and the thermodynamical properties of porous media with water and gas are researched; the comparative analyses of different calculation methods of thermal conductive coefficient have been conducted; an available calculating method is proposed to determine the thermodynamical parameters; the comparisons among the results of the proposed method, the volumetric average method, the self consist method, the Hashin-Strikman method have been made; the proposed method is of the good agreement with the testing result; and it fits to describe the main properties of thermal mechanical conductivity.