Numerically reproduced HE-E experiment of Mont Terri project by Thermo-Hydro-Mechanical coupled model

Abstract

In this study, numerical simulations of HE-E experiment in Mont Terri rock laboratory were performed with Thermo–Hydro–Mechanical (THM) coupled processes. The aim of this study is to validate modelling, understand THM coupled behaviour and verify applicability of material parameters obtained by a column test to the full-scale model. The results of THM and TH coupled analysis are compared, and the influence of fluid and thermal terms/factors on mechanical behaviour is discussed. The analysis code used for THM and TH coupled analysis was CODE_BRIGHT. An axisymmetric analytical model, which allowed modelling of two heaters, was used for the THM and TH coupled model, and their results were compared. As a result, a better reproducibility of relative humidity in the Engineered Barrier System (EBS) and pore water pressure of the bedrock was achieved by performing mechanical coupling. Furthermore, experimental conditions were simulated more realistically, since two heathers and different backfill materials were also modelled in the analysis.