摘要
从辽宁锦州拟建地下储库工程现场钻取典型花岗岩岩芯,进行不同冻结温度(-10℃～-50℃)和不同含水状态(干燥和饱和)的单轴及三轴压缩试验,分析岩石的变形破坏规律、干燥和饱和状态抗压强度以及三轴剪切强度参数c,?值随温度的变化关系。试验结果表明:(1)无论干燥还是饱和试样,微风化花岗岩单轴及三轴抗压强度随着低温温度的降低而提高,但呈现非线性增加的趋势,得到花岗岩抗压强度随低温温度变化的非线性关系拟合式,并认为微风化花岗岩存在一个抗压强度趋于稳定的温度界限值,此值约为-40℃;(2)微风化花岗岩在干燥和饱和条件下,黏聚力c值随温度的降低而增大,在干燥条件下尤为明显。干燥条件下,微风化花岗岩内摩擦角随低温温度降低变化较小,摩擦角基本保持在57°左右,饱和条件下,微风化花岗岩内摩擦角随温度降低而增加,由-10℃～-50℃增长幅度约为3.43%。该研究成果可为液化天然气(LNG)的低温地下存储提供一定的力学参数依据。
The granite samples were drilled form a proposed underground gas storage site in Jinzhou,Liaoning Province.The mechanical tests（uniaxial and triaxial） were conducted under different freezing temperatures（-10 ℃--50 ℃） and different moisture conditions（fully saturated and dry）.Then the law of rock deformation,compressive strength of samples,and the relation between the shear strength parameters and the freezing temperatures were analyzed.The test results show as follows：（1） Whether the granite samples are dry or fully saturated,the uniaxial and triaxial compressive strength increased nonlinearly with the decrease of temperature.There is a threshold temperature below which the strength of granite becomes to stabilize.The effect of the low temperature on the mechanical properties is more obvious for saturated samples.（2） The cohesion increased significantly with the decrease of low temperature.For dry samples,the internal friction angle remained at about 57°.The internal friction angle of fully saturated samples increased about 3.43% when the temperature dropped from-10 ℃ to-50 ℃.In the freezing conditions,the moisture condition has an important impact on the change of the shear strength parameters.The results provide helpful insights for the construction of liquefied natural gas （LNG） storage at low temperature.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2010年第4期787-794,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(50774090)
关键词
岩石力学
花岗岩
低温试验
抗压强度
弹性模量
剪切强度参数
rock mechanics
granite
low temperature compression test
compressive strength
elastic modulus
shear strength parameters
