Numerical study of the THM effects on the near-field safety of a hypothetical nuclear waste repository—BMT1 of the DECOVALEX III project. Part 1: Conceptualization and characterization of the problems and summary of results

M. Chijimatsu (1) , T.S. Nguyen (2) , L. Jing (3) , J. de Jonge (4) , M. Kohlmeier (5) , A. Millard (6) , A. Rejeb (7) , J. Rutqvist (8) , M. Souley (9) , Y. Sugita (10)

1 HC - Hazama Corporation
2 CNSC - Canadian Nuclear Safety Commission
3 KTH - Royal Institute of Technology [Stockholm]
4 Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen
5 LUH - Leibniz Universität Hannover [Hannover]
6 CEA - Commissariat à l'énergie atomique et aux énergies alternatives
7 IRSN - Institut de Radioprotection et de Sûreté Nucléaire
8 LBNL - Lawrence Berkeley National Laboratory [Berkeley]
9 INERIS - Institut National de l'Environnement Industriel et des Risques
10 JNC - Japan Nuclear Cycle Development Institute

Geological disposal of the spent nuclear fuel often uses the concept of multiple barrier systems. In order to predict the performance of these barriers, mathematical models have been developed, verified and validated against analytical solutions, laboratory tests and field experiments within the international DECOVALEX III project. These models in general consider the full coupling of thermal (T), hydraulic (H) and mechanical (M) processes that would prevail in the geological media around the repository. For Bench Mark Test no. 1 (BMT1) of the DECOVALEX III project, seven multinational research teams studied the implications of coupled THM processes on the safety of a hypothetical nuclear waste repository at the near-field and are presented in three accompanying papers in this issue. This paper is the first of the three companion papers, which provides the conceptualization and characterization of the BMT1 as well as some general conclusions based on the findings of the numerical studies. It also shows the process of building confidence in the mathematical models by calibration with a reference T–H–M experiment with realistic rock mass conditions and bentonite properties and measured outputs of thermal, hydraulic and mechanical variables.

Keywords: Numerical model; THM; near-field; nuclear waste repository; DECOVALEX

Domains: Engineering Sciences [physics]; Mechanics [physics.med-ph]

M. Chijimatsu, T.S. Nguyen, L. Jing, J. de Jonge, M. Kohlmeier, et al.. Numerical study of the THM effects on the near-field safety of a hypothetical nuclear waste repository—BMT1 of the DECOVALEX III project. Part 1: Conceptualization and characterization of the problems and summary of results. International Journal of Rock Mechanics and Mining Sciences, 2005, 42 (2005), pp.720-730. ⟨ineris-00175382⟩