Advances in experimental investigation on hydraulic fracturing behavior of bentonite-based materials used for HLW disposal

Abstract : Bentonite-based materials (BBM) in the form of blocks or rings have been commonly proposed as buffer materials for high-level radioactive waste disposal. In a real repository, hydraulic fracturing is likely to be present when the ground water pressure exceeds to hydraulic resistance, the existence of technological gaps increases the risk of hydraulic fracturing. Based on the previous studies of hydraulic fracturing of BBM technological interfaces, the present work systematically analyzes the experimental achievements. Results show that the fracturing pressure of BBM interfaces increases with hydration time, initial dry density, bentonite content overburden pressure, while it decreases with initial water content gap thickness. The temperature effect on hydraulic fracturing depends on the predominant cation of bentonite. For Na-bentonite, the higher temperature leads to the larger swelling pressure, thus the stronger hydraulic resistance. Tensile failure, shear failure synthesis failures are increasingly accepted for hydraulic fracturing mechanism. The hydraulic fracturing of highly compacted BBM is mainly controlled by tensile failure, while the initial shear failure can be found for BBM with a low enough density. Since hydraulic fracturing is expected to occur several times during the repository operation, the long-time monitoring of hydro-mechanical behavior is of vital importance until the technological gaps are completely sealed. Furthermore, the failure mechanism of hydraulic fracturing of BBM should be further researched, as well as the sealing properties of interfaces under thermohydro-mechanically coupled conditions are proposed to be studied thoroughly.
Type de document :
Article dans une revue
Environmental Earth Sciences, Springer, 2016, 75 (9), 〈10.1007/s12665-016-5644-z〉
Liste complète des métadonnées

https://hal-enpc.archives-ouvertes.fr/hal-01573704
Contributeur : Romain Boistel <>
Soumis le : jeudi 10 août 2017 - 14:23:46
Dernière modification le : jeudi 11 janvier 2018 - 06:25:23

Identifiants

Collections

Citation

Yong-Gui Chen, Ling-Yan Jia, Wei-Min Ye, Bao Chen, Yu-Jun Cui. Advances in experimental investigation on hydraulic fracturing behavior of bentonite-based materials used for HLW disposal. Environmental Earth Sciences, Springer, 2016, 75 (9), 〈10.1007/s12665-016-5644-z〉. 〈hal-01573704〉

Partager

Métriques

Consultations de la notice

88