Molecular dynamics data for modelling the microstructural behaviour of compacted sodium bentonites

Abstract

The water content of a bentonite at low saturation (equal to high suction) defines the void ratio of the nano-scale porosity located in the clay interlayers and close to the clay grain surfaces. However, the measured suction curves should not be extrapolated straightforwardly to lower suction values, because, in that case, the presence of water in larger pores between aggregates can be non-negligible. This work analyses the use of data obtained from molecular dynamics models to assess the validity of such extrapolations, and defines the variables needed to compare the results from molecular dynamics and suction experiments. The encouraging agreement contributed to the confidence in the proposed procedure, which enabled a new strategy that uses molecular dynamics data to model the macroscopic behaviour of compacted sodium bentonites.

A New Double-Porosity Macroscopic Model of Bentonite Free Swelling

“…To determine dε m , models are selected that are elastic, incremental (Sánchez et al, 2005) or based on the characterization of the microstructural void ratio e m (= volume of voids associated with m-ML per volume of solids) through a state surface (Fig. 1; Navarro et al, 2021a). dε M can be defined using the Barcelona Basic Model (BBM; Alonso et al, 1990).…”