Thermal Impact on Damaged Boom Clay and Opalinus Clay: Permeameter and Isostatic Tests with μCT Scanning: Special Issue: Thermo-Hydro-Mechanical Effects in Clay Host Rocks for Radioactive Waste Repositories

Guangjing Chen, Tom Maes, Frank Vandervoort, Xavier Sillen, Philippe Van Marcke, Miroslav Honty, M. Dierick, P. Vanderniepen

Research outputpeer-review

Abstract

Within the framework of the TIMODAZ project, permeameter tests and isostatic tests were performed on Boom Clay and Opalinus Clay in order to assess the impact of temperature, pore water composition, and confining stress on the sealing of damaged samples of Boom Clay and Opalinus Clay. A microfocus X-ray computed tomography technique was used to visualize the evolution of the sealing process. Compared to the fast sealing of Boom Clay, the sealing of Opalinus Clay was much slower. The heating showed a significant, favorable impact on the sealing behavior of Opalinus Clay under permeameter test conditions, while the sealing behavior of Boom Clay appeared to be unaffected. Tests performed under isostatic conditions did not reveal a significant influence of a heating–cooling cycle on the sealing behavior of these clays. The reappearance of the fractures or holes in the samples after dismantling confirms earlier observations which showed that after sealing, the original mechanical properties are not recovered. In other words, a heating cycle does not seem to induce healing.
Original languageEnglish
Pages (from-to)87-99
JournalRock Mechanics and Rock Engineering
Volume47
Issue number1
DOIs
StatePublished - Jan 2014

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