Evaluation of specific surface area of bentonite-engineered barriers for Kozeny-Carman law

The impermeability of bentonite is dependent on montmorillonite microstructures and varies with chemical alteration caused by related changes. The Kozeny-Carman equation is viewed as a rational hydraulic model for bentonite because it incorporates microstructure parameters such as specific surface area in addition to macrostructure parameters such as the void ratio. In the study reported here, a technique for measuring the specific surface area of compacted bentonite under constant volume conditions using X-ray diffraction was developed, and the hydraulic conductivity of various bentonite materials was evaluated based on the measurements thus obtained. The applicability of the Kozeny-Carman hydraulic model for evaluation of impermeability of bentonite was clarified.