A new triaxial apparatus for testing soil water retention curves of unsaturated soils under different temperatures

This paper presents a new triaxial apparatus for testing soil water retention curves (SWRCs) under different temperatures. The components of this modified apparatus, as well as the special features of each component, were described. The key part of this innovative apparatus was the temperature control system, which was cooperated with a loading system and a suction control system. Different methods of heating were compared and a more effective method, which used a heating element around the pressure chamber, was consequently adopted. Under different temperatures (25, 40, and 60 °C) and different net mean stresses (40, 100, and 200 kPa), typical results from the SWRCs tests for unsaturated silty clay were presented and analyzed. The experimental results show that the volumetric water content reduces with the increasing temperature at constant suction.