考虑THM耦合的地热能源桩热-力行为分析  

Thermo-mechanical behavior of energy piles based on coupled THM model

作　　者：李峙 刘福深 杨仲轩[1,2,3] 詹伟 LI Zhi;LIU Fushen;YANG Zhongxuan;ZHAN Wei(Computing Center for Geotechnical Engineering(COMEGE),Zhejiang University,Hangzhou 310058,China;Engineering Research Center of Urban Underground Space Development of Zhejiang Province,Hangzhou 310058,China;Research Center of Coastal and Urban Geotechnical Engineering,Zhejiang University,Hangzhou 310058,China;Zhejiang Scientific Research Institute of Transport,Hangzhou 310023,China)

机构地区：[1]浙江大学岩土工程计算中心,浙江杭州310058 [2]浙江省城市地下空间开发工程技术研究中心,浙江杭州310058 [3]浙江大学滨海和城市岩土工程研究中心,浙江杭州310058 [4]浙江省交通运输科学研究院,浙江杭州310023

出　　处：《岩土工程学报》2023年第10期2129-2138,共10页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金面上项目(52179112);国家杰出青年科学基金项目(51825803);浙江省交通运输厅科技计划项目(2021019)。

摘　　要：地热能源桩除了可以承受建筑物的上部结构荷载,还能提供低碳、环保和可持续的制冷/制热功能,因此在土木与能源等行业受到广泛关注。热-水-力(THM)三场耦合效应显著影响能源桩和土体的相互作用及其承载变形特性。利用多孔介质混合物理论推导了THM全耦合的基本控制方程,并通过与饱和非等温固结问题的理论解对比,验证了该耦合问题基于COMSOL有限元分析方法有效性。在此基础上,考虑流体性质随温度的变化和不同的桩土接触模型,开展了基于THM耦合的能源桩二维有限元模型的数值分析,并与离心数值模型和现场试验数据进行对比。计算结果表明该耦合模型不但能预测能源桩中应力、应变和位移场分布与演化规律,还能较好地模拟桩土多场耦合行为。研究结果表明,THM耦合效应对土工分析具有重要影响,研究成果可为能源桩设计、施工及使用过程中所涉及的多场耦合问题提供参考依据。The energy piles can underpin the superstructures and provide low-carbon,environmentally friendly and sustainable cooling/heating functions,leading to ever-growing attention received from the civil and energy industries.The thermo-hydro-mechanical(THM) coupling may significantly affect the interaction between the energy piles and the surrounding soils,and thus the load-bearing and deformation characteristics.In this study,the basic governing equations for full THM coupling are derived based on the standard mixture theory of porous media.The finite element method THM for and its implementation in COMSOL software are verified through comparisons with the analytical solutions to the saturated non-isothermal consolidation problem.Based on the THM coupled framework,a two-dimensional finite element model for the energy piles is further established considering the change of fluid properties with temperature and different pile-soil contact models,and the specific configuration and modeling procedures are described.The results indicate that the proposed model can predict the distribution and evolution of stresses,strains and displacements on the energy piles,and further capture the multi-physical behaviors associated with the piles and soils.This study highlights the importance of the consideration of THM coupling effects,which can provide a useful guidance for the multi-physical problems involved in the design,construction and utilization of the energy piles.

关 键 词：能源桩 热-水-力耦合模型 桩土相互作用 有限元 模型验证 

分 类 号：TU473[建筑科学—结构工程]