摘要
利用MTS815岩石力学试验系统完成了不同温度下的20个花岗岩试样的三轴压缩试验。分析了温度对花岗岩试样的强度特性、变形特性以及破坏特征的影响,能够在实际工程中起到一定的指导作用。试验结果表明:在20℃到40℃的范围,弹性模量随温度升高而降低,泊松比随温度升高而升高,且变化幅度都较大,但当温度超过40℃以后,随温度升高的变化幅度明显降低;随着温度的升高,峰值强度逐渐降低,而且温度对峰值强度的影响随着围压的增加而减弱;内聚力c值随温度升高而降低,内摩擦角φ值随温度升高有升高的趋势,抗剪强度τf大致呈线性减小的关系,且随着正应力的升高,温度对花岗岩抗剪强度的影响有减弱的趋势;花岗岩的变形破坏特征在一般条件下表现为典型的弹脆性体特征,但是在较高围压和较高的温度耦合作用下表现为弹塑性变形-累进性破裂-脆性破坏的特征。
Based on triaxial compression tests of twenty granite samples under different temperatures by MTS815 rock mechanical experiment system,this paper analyzes the influence of temperature on the strength characteristics,deformation characteristics and failure mode of the granite samples,which can have a directive function on practical construction work.Experimental results show that when the temperature ranges from 20 ℃ to 40 ℃,the elastic modulus decreases as temperature increases,but the Poisson ratio increases,both change with a big magnitude,yet when the temperature is over 40℃,the range of variation drops obviously as temperature increases;The peak strength,cohesion C and shear strength τf of specimens decrease as temperature increases,meanwhile the internal friction angle increases;Under the general conditions the failure mode of the granite shows the characteristics of elastic-brittle,but it appears the characteristics of Elastic-plastic deformation,and then the fracture accumulated with finally brittle failure under high confining pressure and high temperature.
出处
《地下空间与工程学报》
CSCD
北大核心
2013年第1期96-101,共6页
Chinese Journal of Underground Space and Engineering
关键词
花岗岩
温度效应
三轴试验
强度特性
变形特性
破坏特征
granite
temperature effect
triaxial tests
strength characteristics
deformation characteristics
failure mode
