A Modified Oedometer with Control Suction and Temperature

Abstract Pressure plate devices have been developed to investigate the hydromechanical behaviour of unsaturated soils using the axis translation technique (ATT). Despite the progress in experimental methods, there are still some problems concerning the ATT application, e.g., the evaporation and condensation of water on cell walls. This investigation discusses a fabricated device-dissolving condensation problem linked to the ATT. A modified suction temperature-controlled oedometer was developed and successfully employed to perform various experiments on unsaturated soils by controlling the vertical net stress, suction, and temperature simultaneously as well as minimizing any problems related to water condensation. The heating system employed for the modified device significantly reduced the water volume errors involving condensation, which varied from 0 to 1.12% in the soil-water characteristic curve (SWCC) test. In addition, the established SWCC of residual granite soil using the modified oedometer was verified by the pressure plate technique.