桩-筏基础中能量桩热-力耦合特性现场试验  

Field tests on thermal-mechanical coupling characteristics of energy pile in pile-raft foundation

作　　者：陆晨凯 孔纲强[1] 孙广超 陈斌 殷高翔 LU Chen-kai;KONG Gang-qiang;SUN Guang-chao;CHEN Bin;YIN Gao-xiang(College of Civil and Transportation Engineering,Hohai University,Nanjing,Jiangsu 210098,China;China Construction Eighth Engineering Division Corp.Ltd.,Shanghai 200135,China;School of Civil and Transportation Engineering,Ningbo University of Technology,Ningbo,Zhejiang 315100,China)

机构地区：[1]河海大学土木与交通学院,江苏南京210098 [2]中国建筑第八工程局有限公司,上海200135 [3]宁波工程学院建筑与交通工程学院,浙江宁波315100

出　　处：《岩土力学》2019年第9期3569-3575,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金项目（No.51778212）~~

摘　　要：能量桩兼具承担上部荷载和传递浅层地温能双重功能,能量桩的换热与承载特性逐渐成为广大工程技术人员关注的重点问题。然而,针对桩-筏基础中能量桩的热-力耦合特性的现场实测资料仍相对较少。提出将桩基完整性检测中的声测管底端连接贯通,作为能量桩的换热管,形成新型能量桩埋管形式;在桩-筏基础中能量桩运行状态下,开展桩-筏基础热力响应特性、能量桩对筏板应力影响的现场试验,实测获得桩身温度、桩身应力及筏板应力变化规律。研究结果表明,该试验条件下,能量桩(1U埋管、有效深度为12.8 m、桩顶埋深为5.5 m)的换热效率约为80~90 W/m;无上部荷载、能量桩加热状态下,筏板上边缘呈现出一定的拉应力,值得工程技术人员关注。Energy pile functions as the bearing capacity of upper load and energy transfer of shallow ground temperature, which becomes one of the most important issues for engineers. However, there is relatively little research on the thermal-mechanical coupling characteristics of energy pile in the pile-raft foundation. One new buried pipe type of energy pile was proposed in this study, in which the bottom end of the acoustic tube was connected as the heat transfer tube. Field tests on the thermal response characteristics and the stress of the raft affected by energy pile were carried out under the operation of the single energy pile in the pile-raft foundation. The temperature and stress of the pile and the stress of the raft were accurately measured. The results showed that the heat transfer efficiency of the energy pile(single U-shaped buried pipe, the effective depth of 12.8 m, pile top depth of 5.5 m) was about 80-90 W/m under the experimental conditions. The tensile stress of the raft on the top side was found during heating without dead load condition, which should be considered during the structure design.

关 键 词：桩-筏基础 能量桩 热力耦合 换热效率 现场试验 

分 类 号：TU473.1[建筑科学—结构工程]