摘要
为探讨温度对桩-土接触面力学性质的影响,自主研制了一套温控桩-土接触面三轴试验仪。基于常规土工三轴仪压力腔,搭建桩-土接触面构件,分别增设桩体和土体温度控制系统,实现非等温条件下桩-土接触面热力耦合特性测试。开展了不同类型、温度荷载等级下桩-砂土接触面热-力耦合特性三轴试验,实测了桩体与土体温度控制精度、桩-土接触面剪切应力、不排水条件下的孔隙水压力以及排水条件下的体积变化等规律,初步验证了试验系统的可靠性和准确性。该试验系统结构简单、拆装方便,可实现温控桩-土接触面三轴试验与常规/温控三轴试验的自由切换。相关研究成果将为桩-土接触面热-力耦合机制与本构模型的建立提供技术支撑。
In order to study the influence of temperature on the mechanical properties of pile-soil interface, a setup of temperature-controlled pile-soil interface triaxial shear test system was developed. The new instrument improves the internal construction of the pressure chamber based on the conventional triaxial shearing instrument. A special structure named pile-soil interface was built in the soil sample and two independent temperature control systems were established for pile and soil, respectively. As a result, the mechanical characteristics of the pile-soil interface under non-isothermal conditions can be tested. A series of triaxial tests were carried out on the thermal-mechanical coupling characteristics of pile-soil interface of sand under different shear conditions and temperature levels. The temperature control accuracy of pile and soil, the shear stress of pile-soil interface, the pore water pressure variation under undrained conditions, and the volume change under drainage conditions were measured. The above results preliminarily verify the accuracy and reliability of the new temperature-controlled pile-soil interface shear test system. The new system has a simple structure and is easy to disassemble. It is also suitable for both temperature-controlled pile-soil interface shear test and conventional(temperature-controlled) triaxial shear test of soil samples. The relevant research results can provide technical support for understanding the thermal-mechanical coupling mechanism and constitutive modelling of the pile-soil interface.
作者
李春红
孔纲强
张鑫蕊
刘汉龙
许晓亮
许俊奎
LI Chun-hong;KONG Gang-qiang;ZHANG Xin-rui;LIU Han-long;XU Xiao-liang;XU Jun-kui(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing,Jiangsu 210024,China;College of Civil Engineering,China Three Gorges University,Yichang,Hubei 443002,China;Nanjing Soil Instrument,Nanjing,Jiangsu 210014,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2019年第12期4955-4962,共8页
Rock and Soil Mechanics
基金
国家自然科学基金（No.51778212）~~
关键词
桩-土接触面
温控
热力耦合
三轴试验
pile-soil interface
temperature control
thermal-mechanical coupling
triaxial shear test
