Thermo-hydro-mechanical behaviour of an expansive bentonite/silt mixture using different suction controlled techniques

This paper presents an experimental study on a bentonite/silt mixture using odometers with suction controlled either by the osmotic technique or by air overpressure at two different temperatures of 20° and 60°C in a suction range between 0 and 8 M Pa. The compression curves permitted us to interpret the influence of the temperature on the different yielding surfaces. The temperature increase rigidified the samples producing a significant increase of the preconsolidation stress. We observed that the compression curves at different imposed suctions converged toward the saturated state for the high applied vertical stresses. The stress from which the compression curves follow the saturated state is called the saturation pressure (P _sat). The P _sat values increased with the temperature increase.