Abstract：The effects of groundwater seepage on the heat transfer and thermo-mechanical coupling characteristics of an energy pile were analyzed using a coupled thermal-mechanical numerical model of the energy pile with seepage. The model shows how the groundwater seepage affects the thermodynamic properties of the energy pile during summer. The results show that in the summer mode the heat transfer of the energy pile with a horizontal seepage velocity of 60 m/a is 1.34 times larger than without seepage. The temperature rise in the pile is then reduced by 9.12%. The groundwater seepage reduces the variations of the pile body displacement, axial force, and the pile side friction while the energy pile rapidly becomes stable. In addition, the groundwater seepage reduces the effect of soil heat in the upstream seepage, but increases the influence of the soil heat in the downstream seepage.
杨卫波, 严超逸, 张来军, 汪峰. 渗流作用下能源桩的换热性能及热-力耦合特性[J]. 清华大学学报（自然科学版）, 2022, 62(5): 891-899.
YANG Weibo, YAN Chaoyi, ZHANG Laijun, WANG Feng. Heat transfer and thermal-mechanical coupling characteristics of an energy pile with groundwater seepage. Journal of Tsinghua University(Science and Technology), 2022, 62(5): 891-899.
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2022, Vol. 62 
