A new method is presented for controlling soil suctions in triaxial tests. The method is based on measurement of suction using thermocouple psychrometers and controlling suctions using the vapour equilibrium technique. The method allows for specimens to be dried/wetted while subjected to externally applied cell pressure and deviator loading. Development of the system and its components is discussed in the text and presented in a series of figures. Operation of the equipment, preparation of the samples, and installation of the specimens are covered. Preliminary test results demonstrate the capability of the system. The results demonstrate that the new suction control method provides a technique whereby suction is controlled and measured in triaxial tests under external loading. Measurements and control of suction at all stages in triaxial testing will allow better constitutive relationships to be evaluated through more generalized stress path testing.; A new method is presented for controlling soil suctions in triaxial tests. The method is based on measurement of suction using thermocouple psychrometers and controlling suctions using the vapour equilibrium technique. The method allows for specimens to be dried/wetted while subjected to externally applied cell pressure and deviator loading. Development of the system and its components is discussed in the text and presented in a series of figures. Operation of the equipment, preparation of the samples, and installation of the specimens are covered. Preliminary test results demonstrate the capability of the system. The results demonstrate that the new suction control method provides a technique whereby suction is controlled and measured in triaxial tests under external loading. Measurements and control of suction at all stages in triaxial testing will allow better constitutive relationships to be evaluated through more generalized stress path testing.
