粘土衬垫中渗透系数与扩散系数的关系

Relationship between hydraulic conductivity and diffusion coefficient of clay liner

摘要: 扩散系数和渗透系数是设计与评价垃圾填埋场衬垫等环境工程研究时需要确定的重要参数。通过分析粘土衬垫材料中渗透系数和扩散系数的物理意义和确定方法,在土多孔介质微观结构分析的基础上得到渗透系数和扩散系数的关系表达式,并基于蒙脱石层间Poiseuille定律得到膨润土有效扩散系数的计算公式。验证表明,在一定精度范围内文中表达式是有效的。得出的渗透系数和扩散系数的关系表达式,对于根据已有渗透系数的研究成果来预测和分析扩散系数是有意义的。

Abstract: Hydraulic conductivity and diffusion coefficient are very important for the design and evaluation of landfill liner.Physical meaning and determined means of hydraulic conductivity and diffusion coefficient were analyzed.Based on microstructure analysis of porous media,the relational expression of hydraulic conductivity and diffusion coefficient was obtained.Then the equation of diffusion coefficient through bentonite was deduced using Poiseuille law.The expression is valid to some degree.It is significative to use the research result of hydraulic conductivity to study diffusion coefficient.