Cement-rock interaction : infiltration of a high-pH solution into a fractured granite core

Within the framework of the HPF project (Hyperalkaline Plume in Fractured Rock) at the Grimsel Test Site (Switzerland), a small scale core infiltration experiment was performed at the University of Bern. A high-pH solution was continuously injected, under a constant pressure gradient, into a cylindr...

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Detalhes bibliográficos
Autores: Soler, Josep M.|||0000-0003-0741-249X, Mäder, Urs K.
Formato: artículo
Fecha de publicación:2010
País:España
Recursos:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:85690
Acesso em linha:https://ddd.uab.cat/record/85690
https://dx.doi.org/urn:doi:10.1344/105.000001531
Access Level:acceso abierto
Palavra-chave:Reactive transport modeling
Cement
Granite
Fracture
High-pH plume
Descrição
Resumo:Within the framework of the HPF project (Hyperalkaline Plume in Fractured Rock) at the Grimsel Test Site (Switzerland), a small scale core infiltration experiment was performed at the University of Bern. A high-pH solution was continuously injected, under a constant pressure gradient, into a cylindrical core of granite containing a fracture. This high-pH solution was a synthetic version of solutions characteristic of early stages in the degradation of cement. The interaction between the rock and the solutions was reflected by significant changes in the composition of the injected solution, despite the negligible pH-buffering capacity, and a decrease in the permeability of the rock. Changes in the mineralogy and porosity of the fault gouge filling the fracture were only minor. Within the new LCS (Long-Term Cement Studies) project at Grimsel, new one-dimensional reactive transport modeling using CrunchFlow has been used to improve the interpretation of the experimental results. Dispersive and advective solute transport, adsorption processes and mineral reaction kinetics have been taken into account. The evolution of solution composition is mainly controlled by dissolution/precipitation reactions. Adsorption processes (cation exchange, surface complexation) only play a role in the very early stages of the experiment.