摘要
为研究红粘土复合地基中CFG桩的变形特性,在CFG桩内埋设混凝土应变计进行监测,结合室内土工试验,分析了红粘土复合地基中CFG桩桩身不同部位应变随荷载、时间的变化规律及其内在作用机理。结果表明:CFG桩在施加上覆荷载之前就存在初始内应力,桩顶下一定部位存在一初始应变零点;红粘土的膨胀性对CFG桩桩体变形有重要影响,复合地基需要较长的时间进行内部变形调整;变形稳定后,桩体中存在两个应变零点,拉压区域交替出现。
In order to study the deformation characteristic of CFG pile in red clay composite foundation,concrete strain gauge was buried inside CFG pile for monitoring.Combined with indoor geotechnical test,the change rule of the strain of CFG pile in different parts with loads and time in red clay composite foundation is analyzed.At the same time,the internal mechanism of CFG pile is concluded.The results show that CFG pile has initial internal stress before applying overlying load and a certain part below the top of pile is the zero point of initial stress.The expandability of red clay exerts significant impact on the deformation of CFG pile,so it takes a long time for composite foundation to adjust internal deformation.After the deformation trends to stable,there are two points of zero strain along pile body,which appear alternately in tensile area.
出处
《路基工程》
2011年第3期9-12,共4页
Subgrade Engineering
基金
国家自然科学基金项目(50778180)
铁道部科技研究开发计划项目(2005K002-B-2-1)
关键词
客运专线
复合地基
红粘土
膨胀性
现场试验
CFG桩
变形特性
passenger dedicated line
composite foundation
red clay
expandability
site test
CFG pile
deformation characteristic
