Influence of pressurized water influx on the hygro-thermal behaviour of an engineered clay barrier in a waste emplacement borehole

This paper presents the results of a series of experiments conducted to examine the hygro-thermal behaviour of a compacted, internally heated engineered clay barrier, consisting of a mixture of bentonitic clay and sand, compacted in a laboratory scale model simulating a waste emplacement borehole located in a granitic rock. The experiments considered the supply of water at a prescribed pressure at the outer cylindrical and plane boundaries of the compacted, engineered clay barrier. The experiments examined the manner in which the water supply conditions influenced the extent of the moisture uptake within the compacted clay barrier. The experimental results presented in this paper include contours of the time-dependent variation of temperature within the granite block, the time-dependent variations of temperature at the midsection level of the internally placed heater and along the axis of the experimental facility, and the residual volumetric moisture content distribution determined at the termination of the experiments.