Analytical evaluation of steady-state solute distribution in through- diffusion and membrane behavior test under non-perfectly flushing boundary conditions  

作　　者：Guannian Chen Yuchao Li Kristin MSample-Lord Shan Tong 

机构地区：[1]School of Civil&Environmental Engineering and Geography Science,Ningbo University,Ningbo,315211,China [2]MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering,College of Civil Engineering and Architecture,Zhejiang University,Hangzhou,310058,China [3]Ningbo ZCONE High-tech Company Limited,Ningbo,315000,China [4]Department of Civil and Environmental Engineering,Villanova University,Villanova,PA,USA

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2024年第1期258-267,共10页岩石力学与岩土工程学报（英文版）

基　　金：The financial support received from the Ministry of Science and Technology of the People’s Republic of China(Grant No.2019YFC1806002);National Natural Science Foundation of China(Grant Nos.42107174,42077241)is gratefully acknowledged.

摘　　要：The through-diffusion and membrane behavior testing procedure using a closed-system apparatus has been widely used for concurrent measurement of diffusion and membrane efficiency coefficients of low-permeability clay-based barrier materials.However,the common assumption of perfectly flushing conditions at the specimen boundaries could induce errors in analyses of the diffusion coefficients and membrane efficiencies.In this study,an innovative pseudo three-dimensional(3D)analytical method was proposed to evaluate solute distribution along the boundary surfaces of the soil-porous disks system,considering the non-perfectly flushing conditions.The results were consistent with numerical models under two scenarios considering different inflow/outflow positions.The proposed model has been demonstrated to be an accurate and reliable method to estimate solute distributions along the bound-aries.The calculated membrane efficiency coefficient and diffusion coefficient based on the proposed analytical method are more accurate,resulting in up to 50%less relative error than the traditional approach that adopts the arithmetic mean value of the influent and effluent concentrations.The retar-dation factor of the clay specimen also can be calculated with a revised cumulative mass approach.Finally,the simulated transient solute transport matched with experimental data from a multi-stage through-diffusion and membrane behavior test,validating the accuracy of the proposed method.

关 键 词：Diffusion testing Membrane behavior Coupled transport Clay barrier Transport modeling 

分 类 号：TU43[建筑科学—岩土工程]