ABSTRACT
Failure conditions in soils at elevated temperatures appear to be highly dependent on stress and temperature history. Temperature-controlled triaxial tests were conducted to gain a deeper understanding of the effects of stress and temperature history on the undrained strength of sand-clay mixtures. Particular attention was paid to the thermal behaviour of the sand-bentonite material considerining the thermal curing time effects. A comprehensive experimental programme was conducted consisting of (i) isotropic drained heating followed by undrained triaxial compression at room temperature and elevated temperatures and (ii) an isotropic drained heating and cooling cycle followed by undrained triaxial compression. The results provide insights into a wide range of thermomechanical behaviours in clays. Data obtained at elevated temperatures were compared with those obtained from tests conducted at ambient temperatures. Based on these comparisons, the study presents and discusses the thermal effects on various behaviours. These include the influence of thermal history on shear strength, experimental evidence of the influence of temperature on pore pressure and the thermal effects on elastic modulus. In addition, the evolution of negative excess pore water pressure as a function of temperature is discussed.
