摘要
为研究岩石峰后力学特性和本构关系,进行岩石的单、三轴压缩全程试验。基于不同阶段和不同破坏类型分别建立"分段本构模型"和"基于破坏类型的损伤软化统计模型"。分段本构模型通过屈服点、峰值点和残余强度点将岩石的应力应变划分为3个阶段,建立分段本构关系函数;基于破坏类型的损伤软化统计模型将岩石的压缩破坏划分为低围压(含单轴)下的环向张拉破坏、高围压下的剪切破坏以及中低围压下的张剪组合破坏,分别选取环向应变、剪切应变和体积应变作为损伤控制变量建立3种破坏类型的本构模型。结果表明,基于破坏类型的损伤软化统计模型能更好地描述岩石峰前及峰后的本构关系,揭示岩石内部损伤的发展过程。
Uniaxial and triaxial compression mechanical tests were carried out to study the mechanical properties and constitutive relation of rock in post peak state. Based on the different stages and different failure types of rock in the uniaxial and triaxial compression mechanical tests,'segmentation constitutive model' and 'damage softening statistic model in different failure types' were built. Yield point,peak point and residual strength point were used to divide the process into three stages in segmentation constitutive model,and the function of constitutive relation was founded. The failure types of rock in compression were divided into tensile failure in low confining pressure,shear failure in high confining pressure,and tensile-shear composite failure in moderate or low confining pressure in the damage softening statistic mode in different failure type,circumferential strain,shear strain and volumetric strain were chosen as damage variables to provide constitutive models,which were proved to be better in describing the relation of stress and strain of rock in the pre-peak and post-peak states,and revealing the damage development process of rock.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2015年第S2期3759-3765,共7页
Chinese Journal of Rock Mechanics and Engineering
基金
国家重点基础研究发展计划(973)项目(2010CB226802)
国家自然科学基金青年科学基金项目(51409224)
国家自然科学基金煤炭联合基金重点项目(51134018)
关键词
岩石力学
峰后
张拉破坏
剪切破坏
张剪破坏
本构关系
rock mechanics
post peak
tensile failure
shear failure
tensile-shear failure
constitutive relation
