Influence of heterogeneities of density on the hydromechanical behaviour of pellet-based bentonite materials in imbibition experiments - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue (Data Paper) Applied Clay Science Année : 2022

Influence of heterogeneities of density on the hydromechanical behaviour of pellet-based bentonite materials in imbibition experiments

Anh Minh Tang
  • Fonction : Auteur
Jean-Michel Pereira
Jean Talandier
  • Fonction : Auteur
Minh Ngoc Vu
  • Fonction : Auteur

Résumé

An experimental investigation on the hydromechanical behaviour of pellet-powder mixtures, candidate materials for sealing the galleries in radioactive waste disposal concepts, was described. Imbibition experiments were performed using a specially-designed column, with square cross-section and glass sides allowing pictures to be taken by a camera. Relative humidity and swelling pressure were measured at different elevations of the column. Three mixtures with an identical pellet volume fraction and various powder volume fractions were used to study the influence of heterogeneities of density on the hydromechanical behaviour of the mixture under repository conditions. Results demonstrated that hydration of the material was dominated by water vapour flux, with pellets and inter-pellet pores not at hydraulic equilibrium. In mixtures with low powder content, the evolution of swelling pressure was controlled by contact forces between pellets. The material progressively lost the initial granular structure upon hydration. Note that hydration was made by imbibition, instead of injecting liquid water at high pressure, to avoid unrealistic liquid water flow rates in the initial large inter-pellet voids. In addition, sensors four times larger than the pellets were used to measure a representative value of swelling pressure.

Dates et versions

hal-04322600 , version 1 (05-12-2023)

Identifiants

Citer

Benjamin Darde, Anh Minh Tang, Jean-Michel Pereira, Patrick Dangla, Jean-Noël Roux, et al.. Influence of heterogeneities of density on the hydromechanical behaviour of pellet-based bentonite materials in imbibition experiments. Applied Clay Science, 2022, 216, pp.106353. ⟨10.1016/j.clay.2021.106353⟩. ⟨hal-04322600⟩
6 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More