不同应力路径下粗粒料力学特性试验研究  

Experimental study of mechanical behavior of a coarse-grained material under various stress paths

作　　者：杨光[1] 孙逊[1] 于玉贞[1] 张丙印[1] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《岩土力学》2010年第4期1118-1122,共5页Rock and Soil Mechanics

基　　金：国家自然科学基金委员会;二滩水电开发有限责任公司雅砻江水电开发联合研究基金项目(No.50639060);清华大学水沙科学与水利水电工程国家重点实验室课题(610103002);高等学校博士学科点专项科研基金资助课题(2006003040)

摘　　要：采用大型三轴试验机,对粗粒料进行了常规三轴、等p和等应力比等不同应力路径的试验。通过对试验结果进行对比分析,研究了粗粒料在不同应力路径下的应力-应变、变形和强度特性,并对粗粒料的卸载体缩现象进行了分析和探讨。结果表明,应力路径对粗粒料的应力-应变和变形特性影响较大,而对强度特性影响较小;卸载体缩主要是由偏应力比η的变化所引起的,与应力路径关系很大。A series of large-scale triaxial tests under different stress paths are performed, including the conventional triaxial tests, constant p tests and constant stress ratio tests. Based on the comparison of test results, the stress-strain, deformation and strength characteristics of a coarse-grained material under different stress paths are investigated. Meanwhile, the phenomena of the volume-contraction in unloading is discussed. The test results indicate that the stress path has obvious influence on the stress-strain and deformation characteristics of the coarse-grained material, but little influence on strength characteristics. The volume-contraction in unloading of the coarse-grained material is caused by the change of deviatoric stress ratio and is related to stress path of test.

关 键 词：粗粒料 应力路径 变形和强度特性 卸载体缩 

分 类 号：TU443[建筑科学—岩土工程]