Development of approaches for modelling coupled thermal–hydraulic–mechanical–chemical processes in single granite fracture experiments
2016 (English)In: Environmental Earth Sciences, ISSN 1866-6280, E-ISSN 1866-6299, Vol. 75, no 19, 1313Article in journal (Refereed) Published
The geological formation immediately surrounding a nuclear waste disposal facility has the potential to undergo a complex set of physical and chemical processes starting from construction and continuing many years after closure. The DECOVALEX project (DEvelopment of COupled models and their VALidation against EXperiments) was established and maintained by a variety of waste management organizations, regulators and research organizations to help improve capabilities in experimental interpretation, numerical modelling and blind prediction of complex coupled systems. In the present round of DECOVALEX (D-2015), one component of Task C1 has considered the detailed experimental work of Yasuhara et al. (Appl Geochem 26:2074–2088, 2011), wherein three natural fractures in Mizunami granite are subject to variable fluid flows, mechanical confining pressure and different applied temperatures. This paper presents a synthesis of the completed work of six separate research teams, building on work considering a single synthetic fracture in novaculite. A range of approaches are presented including full geochemical reactive transport modelling and 2D and 3D high-resolution coupled thermo–hydro–mechanical–chemical (THMC) models. The work shows that reasonable fits can be obtained to the experimental data using a variety of approaches, but considerable uncertainty remains as to the relative importance of competing process sets. The work also illustrates that a good understanding of fracture topography, interaction with the granite matrix, a good understanding of the geochemistry and the associated multi-scale THMC process behaviours is a necessary pre-cursor to considering predictive models of such a system.
Place, publisher, year, edition, pages
Springer, 2016. Vol. 75, no 19, 1313
Code comparison, Coupled analysis, Fluid flow, Fracture, Rock-matrix diffusion, THMC, Diffusion in liquids, Flow of fluids, Geochemistry, Granite, Plant shutdowns, Radioactive waste disposal, Radioactive wastes, Research and development management, Waste disposal, Waste management, Code comparisons, Fracture topographies, Nuclear waste disposal facility, Reactive transport modelling, Rock matrix, Validation against experiments
IdentifiersURN: urn:nbn:se:kth:diva-195300DOI: 10.1007/s12665-016-6117-0ISI: 000385135100014ScopusID: 2-s2.0-84989332469OAI: oai:DiVA.org:kth-195300DiVA: diva2:1045786
QC 201611102016-11-102016-11-022016-11-11Bibliographically approved