摘要
针对青藏铁路北麓河粉质粘土,利用冻融循环全过程电阻率试验设备获取封闭系统下冻融过程电阻率、土体温度场、冻胀融沉变形量全过程曲线,探讨了饱和粉质黏土正冻正融过程电阻率及变形特性。试验结果表明:冻融循环过程中电阻率与冻融变形的变化是实时的、完全同步的,利用电阻率特性研究冻融过程土体结构变化是可行的;每次冻融冻土电阻率随着冻融次数增加呈指数关系减小,融土电阻率随冻融次数增加呈指数关系增加;每次冻胀量与融沉量随冻融次数的增加而减小,平均干密度随冻融次数增加而增加,并且经过5次冻融循环后冻胀融沉量和干密度均趋于稳定。
Using the freeze-thaw cycle apparatus combined with electrical resistivity observation for whole process , repeated freeze-thaw tests in a closed system（i.e, no water supplied） are performed for the saturated silty clay in Beilu River with dry density of 1.62 g/cm^2, in which the complete testing data for the deformation versus time curve, temperatures in different layers and the associated electrical resistivity-time curve are obtained. The experimental results indicate that the changes of resistivity, temperature and deformation during freeze-thaw cycles are real-time and synchronical, which also proves that it is feasible to study the change of soil structure during freezing and thawing by using electrical resistivity method. The resistivity of frozen soil decreases and that of thawed soil increases exponentially with increasing of freezing-thawing times. The amount of frost heave, thaw collapse and average dry density in every cycle rise with increasing of freezing-thawing times, and they trend to be stable after 5 freeze-thaw cycles.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2010年第3期769-774,共6页
Rock and Soil Mechanics
基金
中国科学院冻土工程国家重点实验室开放课题(NoSKLFSE200605)资助
关键词
反复冻融
电阻率
冻胀
融沉
温度
正冻土
正融土
repeated freeze-thaw cycles
electrical resistivity
frost heave
thaw collapse
temperature
freezing soil
thawing soil
