Study on development of pore water pressure and stress-strain characteristics of soft clay under different temperature modes

Temperature has an important influence on pore water pressure and stress-strain relationship of soft clay. Through a self-developed temperature controlled triaxial apparatus, the development of pore water pressure and stress-strain characteristics of soft clay under three different temperature modes including constant temperature, heating and cooling were studied. Under the temperature rise and temperature drop modes, the effects of time interval and confining pressure on the dissipation of pore water pressure, stress-strain relationship, shear strength and elastic modulus of soft clay were emphatically studied. The results show that the dissipation rate and amount of pore water pressure increase with increasing temperature from 10℃ to 70℃ in constant temperature mode. In the heating and cooling modes, the pore water pressure shows a fluctuant decrease and the increases of the time interval and the confining pressure could promote the dissipation of the pore water pressure. In the constant temperature mode, the stress-strain mode changes from strain hardening to strain softening with increasing the temperature, the shear strength increases obviously, and the elastic modulus shows a trend of first decreasing and then increasing. In the heating and cooling modes, the stress-strain mode of soil is strain hardening, and the time interval and the confining pressure obviously have positive influence on the shear strength and the elastic modulus. © 2020, Science Press. All right reserved.