DECOVALEX I - Test Case 3: Calculation of the Big Ben Experiment - Coupled modelling of the thermal, mechanical and hydraulic behaviour of water-unsaturated buffer material in a simulated deposition hole

PNCs large scale laboratory test with an artificial deposition hole has been simulated with finite element calculations with the code ABAQUS. The test comprised water uptake from an artificial rock and heating of a canister in a deposition hole with the diameter 1 m during 5 months. Water content, pore pressure, and total pressure in the buffer was measured during the test. The given data of the material properties were supplemented with results from own laboratory tests in order to determine parameters required for the calculation. The vapour flow process, which is not included in ABAQUS, was implemented and added to the code. After calibration of the properties of the buffer material, a completely coupled thermo-hydro-mechanical calculation of the test was done. The calculated thermal and hydraulic results were in good agreement with measured values, while the prediction of the mechanical response was less good. 13 refs, 47 figs, 8 tabs