Swelling and mechanical erosion of MX-80 bentonite

An approach is proposed for simulating the coupled processes of swelling and mechanical erosion of compacted MX-80 bentonites. The loss of mass at the water?soil interface is described by means of a simplified erosion model, assuming the instantaneous activation of erosion. A double-porosity formula...

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Detalles Bibliográficos
Autores: Navarro Gamir, Vicente, Asensio Sánchez, Laura, Yustres Real, Ángel, Morena Borja, Gema de la, Pintado, Xavier
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/10652
Acceso en línea:http://hdl.handle.net/10578/10652
Access Level:acceso abierto
Palabra clave:Física Química y matemáticas
Ingenierias
Descripción
Sumario:An approach is proposed for simulating the coupled processes of swelling and mechanical erosion of compacted MX-80 bentonites. The loss of mass at the water?soil interface is described by means of a simplified erosion model, assuming the instantaneous activation of erosion. A double-porosity formulation was adopted based on the Barcelona Expansive Model to describe the deformability of the bentonite. In addition, a state surface was introduced to describe the increase in macrostructural porosity caused by the swelling and destructuration of the aggregates. This formulation was implemented in the multiphysics partial differential equation solver Comsol Multiphysics (CM), which was adapted to incorporate a mixed method and a Lagrangian formulation. The ?Deformed Geometry? module of the CM solver allowed for the smooth and continuous updating of the active material domain to the bentonite mass loss defined in the erosion model. Satisfactory data fits were obtained by simulating a variety of pinhole tests on MX-80 samples of various configurations. Thus, although more experimental validation is needed, and the approach could be further improved (introducing, e.g., the effect of water salinity), the obtained results indicate that this method is a useful starting point for describing and quantifying the coupled erosion and swelling of MX-80 bentonites.