Predicting the swelling pressure of MX-80 bentonite

Abstract

This paper proposes a calculation procedure to estimate the swelling pressure of bentonites. The experimental information needed to obtain the estimations can be obtained from relatively conventional tests, including the determination of the water retention curve, and swelling pressure tests using oedometric sample holders. This allows to obtain physically based predictions of the changes in swelling pressure with environment salinity. To facilitate the calculations, an open access spreadsheet in which the proposed approach has been implemented is attached as Supplementary material. A set of significant swelling pressure tests are modelled, obtaining very good fits. The fits not only build confidence in the proposed methodology, but also improve the validation of the hydro-chemo-mechanical formulation on which the proposed procedure is based.