The Effect of Ceramsite Replacement Ratio on Frost-Heave Deformation of Power Transmission and Transformation Foundation in Extreme Condition

Under the impact of frost heave and thaw settlement of seasonal frozen soil, freezing pulling and horizontal tilt of piles often occurs. Aim to the above problems, this paper proposed a material using ceramsite replacement concrete as the foundation to reduce heat exchange with atmosphere. The results showed that when the replacement rate of ceramsite is 80%, the density of the blocks is 1896 kg/m3, which is 19.3% lower than that of plain concrete. Also, the addition of ceramsite significantly reduced the thermal conductivity of concrete. The minimum thermal conductivity of tested blocks is 0.524 W/(m.K), which is 58.6% lower than that of ordinary concrete. Meanwhile, the strength of concrete decreased the addition of ceramsite. When the replacement rate is 80%, the compressive strength and splitting tensile strength are 18.1 and 2.7 MPa, respectively, which are 54.7% and 42.6% lower than that of plain concrete. Taking the climatic environment in the Hexi area as the boundary conditions, a numerical simulation on the design and optimization of the thickness of the insulation system was carried out. It was found that the installation of 2 m insulation concrete can effectively increase the temperature of the soil in extreme environments and avoid frost heave.