Laboratory Test On Thermal Consolidation Properties Of Saturated Silty Clay Under Non-isothermal Conditions

The effect of temperature on the properties of saturated clay is a hot research topic in the field of geotechnical engineering in recent years. It has important value in practical use in energy storage, geothermal resources development, nuclear waste disposal and other important areas. However, domestic researches are still rare in this area, and there are no targeted and systematic researches abroad.Based on the theory of soil mechanics, elastic and plastic mechanics, thermodynamics and function of the least squares fitting, this thesis has made a rather systematic study of the thermal consolidation characteristics of saturated clay under different temperature conditions by laboratory tests,covering consolidation law of heat, thermal properties and pore water pressure mechanism of the evolution in mathematical description.Six successive cycle experiments with the temperature range of 25℃to 50℃and the test sample confining pressure of 50kPa,100kPa and 150kPa has been made with the self-developed thermal consolidation test device including temperature control system developing, including the surrounding pressure systems, back-pressure control system and residual pore water pressure measurement system. Based on the test phenomenon, the thesis has analysed the evolution of the temperature, pore pressure, confining pressure and of cycles under thermal consolidation. Explained the residual pore water pressure and volume strain evolution law consolidation through the mechanism of thermal characteristics.Also, the pore water pressure and volume strain consolidation consolidation in the hot cycle of decay was fitted by least-square method,then a mathematical method and theoretical model was established, which can accurately describe the effects of thermal consolidation history with the temperature change.