Test and analysis of heat transfer characteristics of silicon carbide energy piles in saturated sandy soil foundations
Based on standardized specimen blocks and model experimental tests,heat transfer characteristics of silicon carbide energy piles were investigated.The pile body material ratio of silicon carbide energy piles was determined through the test of thermal conductivity and mechanical properties of pile concrete specimen.Through the high-temperature heat release working condition model test of energy piles in saturated sand foundations,the heat transfer performance of silicon carbide energy piles in saturated sand foundations,as well as the axial-radial temperature distribution and change rule were analyzed.The results show that the thermal conductivity compressive strength and flexural strength of the concrete specimen of pile base are increased by 64.1%,19.9%and 11.4%,respectively when the sand substitution rate of silicon carbide reaches 16.0%,and the ratio of this sand substitution rate is the optimal ratio for the material of the pile body of silicon carbide energy piles.The highest temperature of the silicon carbide energy piles occurs in the middle of the pile body.Compared with ordinary energy piles,the silicon carbide energy piles have higher pile body temperatures,temperature growth rates,and heat transfer power,and show better heat transfer performance.The heat transfer efficiency between pile and soil decreases radially from the pile body to the outside during thermal cycling of the silicon carbide energy piles;after thermal cycling,the soil around the pile shows the phenomenon of heat accumulation,and this phenomenon is gradually strengthened with the approach to the pile body region.The results of the study are expected to provide a test basis for the design and application of silicon carbide energy piles in saturated sandy soil foundations.
energy pilesilicon carbidethermal conductivityheat transfer characteristicsmodel test