The DECOVALEX Project (DEmonstration of COupled models and their VALidation against EXperiment) has been operating since 1992 with the objective of developing thermo-hydro-mechanical coupled computer modelling in order to provide the necessary support for the design of underground radioactive waste repositories. The Project consists of Benchmark Tests which are synthetic models for comparison of different research teams' computer modelling results (verification), and Test Cases which are simulations of actual physical cases to establish whether the modelling does in fact represent the rock reality (validation). An international consortium of Funding Organisations supports the DECOVALEX work, currently the following ten Funding Organisations: BGR/UFZ (Germany), CAS (China), DOE (USA), ENSI (Switzerland), IRSN (France), JAEA (Japan), KAERI (Korea), NDA (UK), NRC (USA) and RAWRA (Czech Republic). In this paper, we explain the 2011–2015 DECOVALEX modelling tasks which cover the range of argillaceous, sedimentary and crystalline rocks.
The purpose of the DECOVALEX project is to conduct thermo-hydro-mechanical-chemical (THMC) coupled numerical modelling to support the safe underground disposal of radioactive waste. The purpose of a radioactive waste repository is to ensure that unacceptable quantities of radionuclides do not migrate to the biosphere through the surrounding rock mass. Accordingly, and in designing the repository, coupled computer modelling is required to take into account the various variables and their interactions in order to be able to ensure the safety of the repository. To confirm that the repository design is appropriate, it is necessary to conduct research to ensure that the different computer models used are suitable—through comparison of the outputs from different codes when studying a synthetic example (verification via a Benchmark Test, BMT) and by comparison with the data from an actual rock mass (validation via a Test Case, TC). This has been the motivation of all the previous and the current DECOVALEX phases.
The project has been continuously in operation since 1992 via a series of research phases: Decovalex I (1992–1995), Decovalex II (1996–1999), Decovalex III (2000–2003), DecovalexTHMC(2004–2007), Decovalex 2011 (2008–2011), and the current phase Decovalex 2015 (2012–2015). An international consortium of Funding Organisations supports the DECOVALEX work. For the current DECOVALEX phase (D–2015), there are ten Funding Organisations: BGR/UFZ (Germany), CAS (China), DOE (USA), ENSI (Switzerland), IRSN (France), JAEA (Japan), KAERI (Korea),NDA(UK),NRC(USA) and RAWRA (Czech Republic).