Application of a concrete thermal pile in cooling the warming permafrost under climate change  

作　　者：Yun-Hu SHANG Fu-Jun NIU Guo-Yu LI Jian-Hong FANG Ze-Yong GAO 

机构地区：[1]State Key Laboratory of Frozen Soil Engineering,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China [2]Da Xing'anling Observation and Research Station of Frozen-Ground Engineering and Environment,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Jagdaqi 165000,China [3]Qinghai Research Institute of Transportation,Xining 810008,China

出　　处：《Advances in Climate Change Research》2024年第1期170-183,共14页气候变化研究进展（英文版）

基　　金：supported by the National Natural Science Foundation of China (42001063,U2268216,42176224);the Natural Science Foundation of Gansu Province (23JRRA660,21JR7RA051);the Science and Technology Project of State Grid Corporation of China (5200-202230098A-1-1-ZN);the program of State Key Laboratory of Frozen Soil Engineering (SKLFSE-ZT-202120).

摘　　要：Permafrost degradation caused by climate warming is posing a serious threat to the stability of cast-in-place pile foundations in warm permafrost regions.Ambient cold energy can be effectively utilized by two-phase closed thermosyphons(TPCTs)to cool the permafrost.Therefore,we installed TPCTs in a cast-in-place pile foundation to create a unique structure called a thermal pile,which effectively utilizes the TPCTs to regulate ground temperature.And we conducted a case study and numerical simulation to exhibit the cooling performance,and optimize the structure of the thermal pile.The purpose of this study is to promote the application of thermal piles in unstable permafrost regions.Based on the findings,the thermal pile operated for approximately 53%of the entire year and effectively reduced the deep ground temperature at a rate of at least-0.1℃per year.Additionally,it successfully raised the permafrost table that is 0.35 m shallower than the natural ground level.These characteristics prove highly beneficial in mitigating the adverse effects of permafrost degradation and enhancing infrastructure safety.Expanding the length of the condenser section and the diameter of the TPCT in a suitable manner can effectively enhance the cooling capability of the thermal pile and ensure the long-term mechanical stability of the pile foundation even under climate warming.

关 键 词：Heat transfer Cold energy Warm permafrost Two-phase closed thermosyphons Cast-in-place pile foundation 

分 类 号：P467[天文地球—大气科学及气象学]