密度及水分状态对黄土状粉土变形特征的影响  

EFFECTS OF DENSITY AND MOISTURE CONTENT ON THE DEFORMATION CHARACTERISTICS OF LOESS-LIKE SILT

作　　者：宋日英[1] 黄志全[1] 陈宇[1] 

机构地区：[1]华北水利水电学院资源与环境学院,郑州450011

出　　处：《工程地质学报》2011年第4期492-497,共6页Journal of Engineering Geology

基　　金：郑州市创新型科技人才培育计划领军人才项目(10LJRC185);教育部留学回国人员科研启动基金

摘　　要：以三门峡地区黄土状粉土为研究对象,通过控制重塑土样的干密度及含水率制备不同状态下的试样,在非饱和土三轴仪上采用不固结不排水试验法,对试样进行试验。试验结果表明:试样的密度及水分状态对土的应力-应变曲线特征有着重要影响,在不同干密度及含水率下分别出现应力软化和应力硬化两种曲线形态;试样的破坏偏应力随干密度的增大而升高、随含水率的降低而升高,含水率为7%时候的破坏偏应力是含水率13%的2倍左右;非饱和状态下,试样的剪切破坏面以单一及双剪切面为主,且在一定含水率下,试样的破坏变形形态会随干密度的不同而出现剪胀和剪缩两种现象。Take Loess-like silt in areas of Sanmenxia for the study,using unconsolidated undrained shear test method on the unsaturated soils triaxial test instrument,the test were carried by controlling the different dry density and moisture content of the remoded soil preparing to different state of the samples.The results are as follows,Density and moisture content of the test specimen has an important impact on the stress-strain curve of loess-like silt and there will be two kinds of curves such as stress softening curve and stress hardening curve under the different density and moisture content;Partial destruction stress of the test specimen is increasing while the density is increasing and is increasing while the moisture content is decreasing,partial destruction stress of specimen with 7% moisture content is about twice that of specimen with 13% moisture content.Under unsaturated condition,the simple and double-shear planes are main types of the shear failure planes of the test specimen,and under certain moisture content,the destruction shape of the test specimen can appear two kind of phenomena of the dilating and the shrinking with the different dry density.

关 键 词：黄土状粉土 应力-应变曲线 干密度 含水率 偏应力 

分 类 号：TU411[建筑科学—岩土工程]