EXPERIMENTAL STUDY ON TEMPERATURE EFFECT OF CONSOLIDATION AND PERMEABILITY OF COASTAL SOFT SOIL

With the rise of energy underground engineering in coastal areas, it is of great significance to study the influence of temperature(heating) on the engineering characteristics of coastal soils. Based on the temperature-controlled consolidation and permeation instrument, combined consolidation and permeation tests were conducted for typical coastal soft soil at room temperature and elevated temperatures to analyze the effects of temperature rise on the consolidation settlement, permeability coefficient, and pore pressure dissipation of soil samples. The results show that the residual pore pressure of the heating group is higher than that of the normal temperature group, the permeability coefficient increases, and the excess pore pressure dissipates faster, so the peak pore pressure of the heating group is lower than that of the normal temperature group. With the increase of temperature, the skeleton structure of soil is impacted, the elastic deformation range of soil is reduced, and the soil is more prone to yield. Under the same consolidation pressure, the settlement of the heating group is greater than that of the normal temperature group. The permeability coefficient decreases with the increase of consolidation pressure, and the increase of temperature changes the viscosity coefficient of pore water, so that the water in the soil is more easily discharged. However, the permeability coefficient increases with the increase of temperature, and a 15 ℃ increase makes the permeability coefficient of coastal soft soil increase about 3.7 times, while the permeability index changes from 0.37 to 0.71.