Alteration of Bentonite Reacted with Cementitious Materials for 5 and 10 years in the Mont Terri Rock Laboratory (CI Experiment)

The cement–clay interaction (CI) experiment was carried out at the Mont Terri rock laboratory to complement current knowledge on influence that cementitious materials have Opalinus Clay (OPA) and bentonite (MX). Drill cores including interface of OPA, concrete (LAC = low-alkali binder, OPC ordinary Portland cement), MX, which interacted for 4.9 10 years, were successfully retrieved after drilling, detailed analyses performed evaluate potential mineralogical changes. saturated compacted bentonites in core samples divided into ten slices, profiling direction towards interface, extent spatial variation alteration bentonite. Regarding mineral compositions bentonite, cristobalite dissolved within a range mm from both LAC-MX OPC-MX, while calcite precipitated near OPC-MX. In secondary products containing Mg (e.g., M-S-H) also 20 interface. These alterations developed during first with very limited progress observed subsequent 5 years. Detectable changes nature montmorillonite (i.e., formation illite or beidellite, increase layer charge) did not occur years interaction.