摘要
使用河海大学TSW-40型真三轴仪,对粗粒土分别进行平面应变和常规三轴压缩试验,研究了粗粒土在平面应变条件下的应力-应变关系及各种应变之间的关系,包括:主应力差1-3(2-3)与大主应变1、主应力比1/3(2/3)与大主应变1、球应力p与体积应变v、偏应力q与偏应变s、广义应力比q/p与广义剪应变s、小主应变3与大主应变1、体积应变v与广义剪应变s之间的关系。试验结果表明,对于相同的3,平面应变试验的(1-3)(或1/3)-ε1曲线位于常规三轴压缩试验相应曲线的上方;3大的(1-3)(或2-3)-1曲线在上方,而3大的1/3(或2/3)-1曲线在下方;对于相同的3,在相同的1下,平面应变条件下的小主应力方向膨胀量要比常规三轴压缩条件下的大;产生相同的s时,3越大,v越大,对于相同的3,平面应变条件下的v要比常规三轴压缩条件下的大;粗粒土在平面应变和常规三轴压缩条件下加荷时,具有归一化的双曲线应力-应变关系。研究表明,采用非线性弹性模型计算粗粒土的平面应变问题时,有必要考虑弹性模量E和泊松比的各向异性。
Plane strain and conventional triaxial compression tests are performed on coarse-grained soil by the TSW-40 type true triaxial apparatus in Hohai University.The stress-strain relations and relationships between different strains of coarse-grained soil in plane strain condition are studied,including the relations between principal stress difference 1-3（or 2-3） and maximum principal strain 1,principal stress ratio 1/ 3（or 2/ 3） and maximum principal strain 1,spherical stress p and volumetric strain v,deviator stress q and deviator strain s,generalized stress ratio q/p and generalized shear strain s,maximum principal strain 3and maximum principal strain 1,volumetric strain vand generalized shear strain s.The experimental results show that with the same 3,the 1-3（or 1/ 3） curves in plane strain tests lie above those in conventional triaxial tests;the 1-3（or 2-3） curves with larger σ3 lie above those with smaller 3,while the 1/ 3（or 2/ 3） curves with larger 3 lie below those with smaller 3;at the same σ3 and 1,the expansion in the direction of minor principal stress in plane strain condition is larger than that in conventional triaxial condition;at the same s,the larger the 3 is,the larger the v would be,and the volumetric strain vin plane strain condition would be larger than that in conventional triaxial compression condition at the same 3.There is a uniform hyperbolic stress-strain relationship in both plane strain and conventional triaxial compression conditions.It is proved that it is necessary to consider the anisotropy of elastic modulus E and Poisson’s ratio in the calculation of plane strain problems of coarse-grained soil by nonlinear elastic models.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2013年第1期101-108,共8页
Rock and Soil Mechanics
基金
住房和城乡建设部科学技术项目(No.2012-K3-9)
水利部公益性行业科研专项"高心墙堆石坝安全性评价技术研究"(No.200801133)
重庆交通大学水利水运工程教育部重点实验室暨国家内河航道整治工程技术研究中心开放基金资助(No.SLK2012B05)
常州工学院科研基金项目(No.YN1012)
江苏技术师范学院青年科研基金(No.KYY11091)
关键词
平面应变
粗粒土
应力-应变
弹性模量
各向异性
plane strain
coarse-grained soil
stress-strain
elastic modulus
anisotropy
