Grain crushing and its effects on rheological behavior of weathered granular soil  

作　　者：陈晓斌 张家生 

机构地区：[1]School of Civil Engineering,Central South University [2]National Engineering Laboratory for High Speed Railway Construction(Central South University)

出　　处：《Journal of Central South University》2012年第7期2022-2028,共7页中南大学学报（英文版）

基　　金：Project(50908233) supported by the National Natural Science Foundation of China;Project(200413) supported by Communication Science and Technology Fund of Hunan Province,China

摘　　要：To disclose the grain crushing effects on the weathered granular soil rheological behavior,a series of rheological tests (odometer compression and triaxial shearing) were carried out.At the same time,the sieving analysis tests of these specimens were also executed before and after tests,and the grain crushing degree,Br and n5,were collectively adopted to estimate the grain crushing.The grain crushing degree depends on the stress path,stress level,and load time,especially,the longer load time and more intensive gradient shearing path will increase the grain crushing quantity.The Hardin crushing degrees Br are 0.191,0.118 and 0.085 in the ordinary compression,rheological compression and triaxial rheological shearing,respectively;The grain crushing degrees n5 are 1.9,1.4 and 1.32,respectively.The strain softening phase indicates the grain crushing and diffusive collapse,and the strain hardening phase indicates the rearrangement of these crushed grains and formation of new bearing soil skeleton.The rheological deformation of granular soil can be attributed to the coarse grain crushing and the filling external porosity with crushed fragments.To disclose the grain crushing effects on the weathered granular soil rheological behavior, a series of rheological tests （odometer compression and triaxial shearing） were carried out. At the same time, the sieving analysis tests of these specimens were also executed before and after tests, and the grain crushing degree, Br and n5, were collectively adopted to estimate the grain crushing. The grain crushing degree depends on the stress path, stress level, and load time, especially, the longer load time and more intensive gradient shearing path will increase the grain crushing quantity. The Hardin crushing degrees Br are 0.191, 0.118 and 0.085 in the ordinary compression, rheological compression and triaxial rheological shearing, respectively; The grain crushing degrees n5 are 1.9, 1.4 and 1.32, respectively. The strain softening phase indicates the grain crushing and diffusive collapse, and the strain hardening phase indicates the rearrangement of these crushed grains and formation of new bearing soil skeleton. The rheological deformation of granular soil can be attributed to the coarse grain crushing and the filling external porosity with crushed fragments.

关 键 词：grain crushing degree rheological behavior weathered granular soil tri-axial rheological tests odometer compressiontest 

分 类 号：TU411[建筑科学—岩土工程]