温度和掺砾量对冻结掺砾黏土单轴压缩特性影响的试验研究  

Influence of temperature and gravel content on uniaxial compressive characteristics of frozen gravel-mixed clays

作　　者：张勇敢 鲁洋[1] 刘斯宏[1] 杨蒙[1] ZHANG Yonggan;LU Yang;LIU Sihong;YANG Meng(College of Water Conservancy and Hydropower Engineerings Hohai University,Nanjing,Jiangsu 210098,China)

机构地区：[1]河海大学水利水电学院

出　　处：《岩石力学与工程学报》2019年第11期2357-2364,共8页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金雅砻江联合基金重点支持项目(U1765205);国家重点研发计划(2017YFC0404805)~~

摘　　要：为探究冻结掺砾黏土的单轴压缩特性,开展不同温度、不同掺砾量条件下冻结掺砾黏土的单轴压缩试验。试验结果表明:温度和掺砾量对冻结掺砾黏土应力–应变关系、单轴抗压强度、破坏应变和弹性模量影响显著,单轴加载条件下试样均表现为脆性破坏,且掺砾量越小,脆性破坏特征越显著。冻结掺砾黏土的单轴抗压强度随温度的降低而增大,随掺砾量的增加而减小,其变化幅度与试样内部黏土–砾石基质的空间结构分布紧密相关;破坏应变随掺砾量的增加而减小,随温度的变化其规律并非一致,而是显著依赖于掺砾量的大小;弹性模量呈现出随温度的降低而近似线性增大、随掺砾量的增加先增大后减小的变化趋势,且存在一个与温度相关的临界掺砾量。In order to study the mechanical properties of frozen gravel-mixed clays,a series of uniaxial compression tests on frozen gravel-mixed clays were conducted with different temperatures and gravel contents.The test results show that the stress-strain response,uniaxial compressive strength,failure strain and elastic modulus are strongly affected by the temperature and gravel content of the specimens.Under uniaxial loading,the specimens present a typical pattern of brittle failure,and the smaller the gravel content is,the more significant the brittle failure characteristics are.The uniaxial compressive strength of the frozen gravel-mixed clay increases with decreasing both the temperature and the gravel content,and the variation degree is closely related to the structure distribution of clay-gravel.The failure strain decreases with increasing the gravel content while the effect of the temperature on the failure strain shows different characteristics under different gravel contents.The elastic modulus shows a quasi-linear increase with decreasing the temperature,and increases first and then decreases with increasing the gravel content.It is worth noting that the critical value of the gravel content depends on the temperature.

关 键 词：土力学 冻结掺砾黏土 温度 掺砾量 应力–应变关系 单轴抗压强度 破坏应变 弹性模量 

分 类 号：TU445[建筑科学—岩土工程]