(1. College of Transportation Science and Engineering，Nanjing Tech University，Nanjing，Jiangsu 210009，China；2. Changzhou Vocational Institute of Textile and Garme，Changzhou，Jiangsu 213164，China；3. Technology Development Center，Jiangsu Provincial Department of Housing and Urban Rural Construction，Nanjing，Jiangsu 210036，China)
Abstract：The energy pile，integrating the heat exchange tubes of the ground source heat pump and the pile foundation of the building，has better heat transfer performance with a larger length of the energy pile，but at the same time，the coupled thermal-mechanical behaviors become more complicated and are paid little attention to. Taking a 40 m long floating energy pile of the Kunshan energy pile project as an example，a simplified thermo-mechanical coupling numerical model was established，and the bearing performance of the pile and the displacement behavior of the pile top during the whole process of load-temperature coupling were studied. The results indicate that the load transfer characteristics such as the pile axial force，shaft resistance and settlement of the floating energy pile are influenced obviously by temperature change when the load is lower than 50% of the ultimate load Pu. When the load is equal to 25% Pu and 50% Pu，the maximum change of the axial force of the floating energy pile respectively increase to 3.1 times and 1.6 times，and the settlement change range of the pile is over 66% and 25% respectively. When the load level of the pile is higher than 75% Pu，the pile load will have dominant effect on load transfer characteristics of the floating energy pile，and the changes of the axial force and shaft resistance of the energy pile will gradually decrease induced by load cooling/heating effect. Due to that the settlement of the energy pile will increase obviously under cooling，it is not suitable for the floating energy to continue to play a role. It is suggested that the load should be controlled less than 75%Pu while considering a engineering pile as an energy pile and that the thermo-mechanical effect on bearing performance of the energy pile should be concerned.
蒋 刚1，李仁飞1，王 昊1，陈 根1，2，路宏伟3，邵 东1. 摩擦型能源桩热–力耦合全过程承载性能分析[J]. 岩石力学与工程学报, 2019, 38(12): 2525-2534.
JIANG Gang1，LI Renfei1，WANG Hao1，CHEN Gen1，2，LU Hongwei3，SHAO Dong1. Numerical analysis of the bearing capacity of floating energy piles during the full#br# process of thermal-mechanical coupling. , 2019, 38(12): 2525-2534.
[1] 余 闯，潘林有，刘松玉，等. 热交换桩的作用机制及其应用[J]. 岩土力学，2009，30(4)：933–937.(YU Chuan，PAN Linyou，LIU Songyu，et al. Working mechanism and application of heat exchanger piles[J]. Rock and Soil Mechanics，2009，30(4)：933–937.(in Chinese))
[2] BRANDL H. Energy foundations and other thermo-active ground structures[J]. Géotechnique，2006，56(2)：81–122.
[3] LALOUI L，NUTH M，VULLIET L. Experimental and numerical investigations of the behaviour of a heat exchanger pile[J]. International Journal for Numerical and Analytical Methods in Geomechanics，2006，30(8)：763–781.
[4] BOUME-WEBB P J，AMATYA B，SOGA K. et al. Energy pile test at Lambeth College，London：Geotechnical and thermodynamic aspects of pile response to heat cycles[J]. Géotechnique，2009，59(3)：237–248.
[5] 桂树强，程晓辉. 能源桩换热过程中结构响应原位试验研究[J]. 岩土工程学报，2014，36(6)：1 087–1 094.(GUI Shuqiang，CHENG Xiaohui. In-situ tests on structural responses of energy piles during heat exchanging process[J]. Chinese Journal of Geotechnical Engineering，2014，36(6)：1 087–1 094.(in Chinese))
[6] 路宏伟，蒋 刚，王 昊，等. 摩擦型能源桩荷载–温度现场联合测试与承载性状分析[J]. 岩土工程学报，2017，39(2)：334–342. (LU Hongwei，JIANG Gang，WANG Hao，et al. In-situ tests and thermo-mechanical bearing characteristics of friction geothermal energy piles[J]. Chinese Journal of Geotechnical Engineering，2017，39(2)：334–342.(in Chinese))
[7] OUYANG Y，SOGA K，LEUNG Y F. Numerical back-analysis of energy pile test at Lambeth College，London[C]// Geo-Frontiers 2011：Advances in Geotechnical Engineering. Dallas：Geotechnical Special Publication，2011：440–449.
[8] KNELLWOLF C，PERON H，LALOUI L. Geotechnical analysis of heat exchanger piles[J]. Journal of Geotechnical and Geoenvironmental Engineering，2011，137(10)：890–902.
[9] MIMOUNI T，LALOUI L. Towards a secure basis for the design of geothermal piles[J]. Acta Geotechnica，2014，9(3)：355–366.
[10] PLASEIED N. Load-transfer analysis of energy foundations[M. S. Thesis][D]. Boulder：University of Colorado，2012.
[11] 黄胤培，蒋 刚，路宏伟，等. 基于指数模型的能源桩热–力耦合荷载传递法[J]. 南京工业大学学报：自然科学版，2019，41(1)：96–103.(HUANG Yipei，JIANG Gang，LU Hongwei et al. Thermo- mechanical coupling load transfer method of energy pile based on exponential model[J]. Journal of Nanjing TECH University：Natural Science，2019，41(1)：96–103.(in Chinese))
[12] 徐新丽，蒋 刚，路宏伟，等. 能源桩热–力半耦合弹性理论分析方法[J]. 南京工业大学学报：自然科学版，2019，41(1)：121–128.(XU Xinli，JIANG Gang，LU Hongwei，et al. Elasticity theory of energy pile under thermal-mechanical semi-coupling[J]. Journal of Nanjing TECH University：Natural Science，2019，41(1)：121–128.(in Chinese))
[13] SURYATRIYASTUTI M E，MROUEH H，BURLON S. Understanding the temperature-induced mechanical behaviour of energy pile foundations[J]. Renewable and Sustainable Energy Reviews，2012，16(5)：3 344–3 354.
[14] GASHTI E H N，MALASKA M，KUJALA K. Evaluation of thermo- mechanical behaviour of composite energy piles during heating/cooling operations[J]. Engineering Structures，2014，75(2)：363–373.
[15] 郝耀虎，孔纲强，彭怀风，等. 桩端约束对桩身热力学特性影响的模拟分析[J]. 防灾减灾工程学报，2017，37(4)：532–539.(HAO Yaohu，KONG Gangqiang，PENG Huaifeng，et al. Analysis of thermo-mechanical behavior of single pile influenced by pile tip constraint[J]. Journal of Disaster Prevention and Mitigation Engineering，2017，37(4)：532–539.(in Chinese))
[16] 王成龙，刘汉龙，孔纲强，等. 不同刚度约束对能量桩应力和位移的影响研究[J]. 岩土力学，2018，39(11)：4 261–4 267.(WANG Chenglong，LIU Hanlong，KONG Gangqiang，et al. Study on stress and displacement of energy pile influenced by pile tip stiffness[J]. Rock and Soil Mechanics，2018，39(11)：4 261–4 267.(in Chinese))
[17] TSETOULIDIS C，NASKOS A，GEORGIADIS K. Numerical investigation of the mechanical behaviour of single energy piles and energy pile groups[C]// Energy Geotechnics. London：Taylor & Francis Group，2016：569–575.
[18] DONNA A D，LALOUI L. Numerical analysis of the geotechnical behaviour of energy piles[J]. International Journal for Numerical and Analytical Methods in Geomechanics，2015，39(8)：861–888.
[19] NG C W W，MA Q J，GUNAWAN A. Horizontal stress change of energy piles subjected to thermal cycles in sand[J]. Computers and Geotechnics，2016，78：54–61.
[20] 费 康，洪 伟，钱 健，等. 循环温度作用下砂土地基能量桩的长期工作特性[J]. 防灾减灾工程学报，2017，37(4)：525–531.(FEI Kang，HONG Wei，QIAN Jian，et al. Long-term performance of energy piles subjected to cyclic thermal loading in sand[J]. Journal of Disaster Prevention and Mitigation Engineering，2017，37(4)：525–531.(in Chinese))
[21] 徐先坤，水伟厚，陈国栋. 软土地区超长灌注桩竖向承载性能实测研究[J]. 岩土工程学报，2011，33(2)：502–507.(XU Xiankun，SHUI Weihou，CHEN Guodong. Vertical bearing capacity of super-long bored Piles in soft soil area[J]. Chinese Journal of Geotechnical Engineering，2011，33(2)：502–507.(in Chinese))
[22] BATINIA N，ALESSANDRO F R L，CONTI P，et al. Energy and geotechnical behaviour of energy piles for different design solutions[J]. Applied Thermal Engineering，2015，86：199–213.
[23] 王彬彬，路宏伟，洪 鑫，等. 地热桩荷载–温度作用下单桩沉降特性数值分析[J]. 南京工业大学学报：自然科学版，2016，38(1)：89–95.(WANG Binbin，LU Hongwei，HONG Xin，et al. Numerical analysis on thermo-mechanical settlement characteristics of geothermal energy single pile[J]. Journal of Nanjing TECH University：Natural Science，2016，38(1)：89–95.(in Chinese))
[24] 费 康，钱 健，洪 伟，等. 黏土地基中能量桩力学特性数值分析[J]. 岩土力学，2018，39(7)：2 651–2 661.(FEI Kang，QIAN Jian，HONG Wei et al. Numerical analysis of mechanical behavior of energy piles in clay[J]. Rock and Soil Mechanics，2018，39(7)：2 651–2 661. (in Chinese))
[25] 张 楠，夏胜全，侯新宇，等. 土热传导系数及模型的研究现状和展望[J]. 岩土力学，2016，37(6)：1 550–1 559.(ZHANG Nan，XIA Shengquan，HOU Xinyu，et al. Review on soil thermal conductivity and prediction model[J]. Rock and Soil Mechanics，2016，37(6)：1 550–1 559.(in Chinese))
[26] 中华人民共和国行业标准编写组. DG/TJ08–2119—2013上海市工程建设规范–地源热泵系统工程技术规程[S]. 上海：[s. n.]，2013.(The Professional Standards Compilation Group of People?s Republic of China. DG/TJ08–2119—2013 Technical specification for ground-source heat pump system[S]. Shanghai：[s. n.]，2013.(in Chinese))
[27] 中华人民共和国行业标准编写组. JGJ/T 438—2018 桩基地热能利用技术标准[S]. 北京：中国建筑工业出版社，2018.(The Professional Standards Compilation Group of People?s Republic of China. JGJ/T 438—2018 Technical standard for utilization of geothermal energy through piles[S]. Beijing：China Architecture and Building Press，2018.(in Chinese))
[28] RANDOLPH M F，WROTH C P. Application of the failure state in undrained simple shear to the shaft capacity of driven piles[J]. Géotechnique，1981，31(1)：143–157.
[29] POULOS H G. Pile behavior-theory and application[J]. Géotechnique，1989，39(39)：365–415.
[30] 中华人民共和国国家标准编写组. GB 50010—2010 混凝土结构设计规范[S]. 北京：中国建筑工业出版社，2010.(The National Standards Compilation Group of People?s Republic of China. GB 50010—2010 Code for design of concrete structures[S]. Beijing：China Architecture and Building Press，2010.(in Chinese))
[31] 陈 根. 长桩型能源桩热–力耦合承载性能的现场测试与数值分析[硕士学位论文][D]. 江苏：南京工业大学，2017.(CHEN Gen. Field test and numerical analysis of thermal-mechanical coupling bearing capacity of long pile type energy pile[M. S. Thesis][D]. Jiangsu：Nanjing Tech University，2017. (in Chinese))
[32] 中华人民共和国行业标准编写组. JGJ 94—2008 建筑桩基技术规范[S]. 北京：中国建筑工业出版社，2008.(The Professional Standards Compilation Group of People?s Republic of China. JGJ 94—2008 Technical code for building pile foundations[S]. Beijing：China Architecture and Building Press，2008.(in Chinese))
[33] 中华人民共和国行业标准编写组. JGJ 106—2014 建筑基桩检测技术规范[S]. 北京：中国建筑工业出版社，2014.(The Professional Standards Compilation Group of People?s Republic of China. JGJ 94—2008 Technical code for testing of building foundation piles[S]. Beijing：China Architecture and Building Press，2014.(in Chinese))
2019, Vol. 38 
