Experiments on water sorption and dilatation

Previous studies of water sorption and dilatation were concerned on syntetic zeolites (mainly clinoptilolite). Sorption and dilatation curves are characteristic for groups of swelling materials and natural/syntetic zeolites. The aim of this study is to determine the behaviour of smectite-rich clay materials during sorption and dilatation experiments. Eight sets of clay materials were used in the experiments. Six samples represent bentonites s. s. (argillized pyroclastics). These materials were sampled at Rokle deposit, Nepomysl deposit, Trebusice deposit, Cerny vrch deposit, Krasny dvur deposit and Strance deposit (Czech Republic). All studied bentonites contain mainly montmorillonite with Ca2+ and Mg2+ as dominant interlayer ions. Kaolinite and illite are subordinate. Two samples represent sedimentary montmorillonite-rich clays from Marsov and Zelena deposit near Skalna (Czech Republic). These clays contain smectite ≥ illite ≥ kaolinite. (authors)