Influence of Microcracking of Host Rock on the Hydromechanical Responses of Underground Structures: Constitutive Modeling and Numerical Simulations
Résumé
This paper presents a numerical modeling accounting for the effect of cracking on both mechanical and hydraulic properties of unsaturated rocks. Firstly, the constitutive model developed by Bui, et al. [3], established in the framework of thermodynamics of porous media, is recalled. Its main feature is that damage intervenes on both mechanical behavior and hydraulic properties (water retention curve and hydraulic conductivity). Secondly, the model is validated against experimental data on an argillaceous rock. Finally, this constitutive model is implemented into a domestic finite element code to study numerically the evolution of hydromechanical responses of a radioactive waste underground gallery during a simplified life cycle. Numerical simulations demonstrate the consistency of the model and highlight the influence of desaturation on the hydromechanical behavior of the gallery.