Characteristics of cumulative deformation of saturated soft clay considering temperature effect

The temperature-controlled cyclic triaxial tests on Ningbo soft clay are carried out to study cumulative deformation, pore pressure, damping ratio and dynamic modulus of soils under different temperatures and undrained conditions. A strain constitutive model is developed considering the effects of temperature, initial static deviator stress, confining pressure, overconsolidation ratio and other factors, and the relationship between the model parameters and temperature is obtained. It is shown that the temperature has great influence on the cumulative plastic deformation, pore pressure, damping ratio and dynamic modulus of soils. The cumulative plastic strain, pore pressure and damping ratio decrease gradually with the increase of temperature, and the dynamic elastic modulus increases with the increase of temperature, thus heat hardening characteristic is revealed. In addition, the calculated results using the strain constitutive model considering the influence of temperature are consistent with the experimental ones, which verify the rationality of the model. Furthermore, the proposed model can be used to predict the cumulative plastic strain results of soils under the same condition of arbitrary temperature.