Modelling of the interaction between chemical and mechanical behaviour of ion exchange resins incorporated into a cement-based matrix

¹ CEA, DEN, DPC, SECR, Laboratoire d’Etude du Comportement des Béns et des Argiles, F-91191, Gif-sur-Yvette, France
² Polytech Lille - LML UMR 8107, Bd Paul Langevin, 59650 Villeneuve d'Ascq, France

Abstract

In this paper, we present a predictive model, based on experimental data, to determine the macroscopic mechanical behavior of a material made up of ion exchange resins solidified into a CEM III cement paste. Some observations have shown that in some cases, a significant macroscopic expansion of this composite material may be expected, due to internal pressures generated in the resin. To build the model, we made the choice to break down the problem in two scale’s studies. The first deals with the mechanical behavior of the different heterogeneities of the composite, i.e. the resin and the cement paste. The second upscales the information from the heterogeneities to the Representative Elementary Volume (REV) of the composite. The heterogeneities effects are taken into account in the REV by applying a homogenization method derived from the Eshelby theory combined with an interaction coefficient drawn from the poroelasticity theory. At the first scale, from the second thermodynamic law, a formulation is developed to estimate the resin microscopic swelling. The model response is illustrated on a simple example showing the impact of the calculated internal pressure, on the macroscopic strain.