岩土力学2012，Vol.33Issue(10)：2942-2946,5.
南阳膨胀土裂隙面强度试验研究
Test study of shear strength of fissure-plane in Nanyang expansive soil
摘要
Abstract
Fissures which almost exist in all of expansive soils always result in failure of expansive soil slope. Shear strength characteristics of fissure-plane are studied; and a new triaxial test method is recommended with typical expansive soil taken from Nanyang section of middle route project for South-to-North Water Transfer. The computerized tomography (CT) technology is firstly introduced to shear strength test of fissure-plane. The real failure stress of fissure-plane is analyzed accurately through measurement of the fissure-plane's real occurrence by CT scanning; and shear strength parameters determined method is provided for triaxial test of fissure-plane. The test results show that the peak strength of fissure-plane is much lower than that of bilateral expansive soil without fissures and even smaller than residual strength of bilateral expansive soil without fissures. The reasons of these phenomena are that gray clay in fissures has higher water content, smectite content and particles orientation degree. Leaching behavior of groundwater generates three aspect alternations to fissures. In microscopic view, leaching changes ferric iron oxide in expansive soil to ferrous oxide and that results gray clay in fissures whose color is different from expansive soil besides fissures. In mesoscopic view, mineral composition and particles arrangement of expansive soil have been modified by leaching and filling material in fissures have higher smectite content and particles orientation degree. In macroscopic view, factors mentioned above result in significant difference between fissure-plane and bilateral expansive soil.关键词
南水北调中线工程/膨胀土/裂隙面/抗剪强度/CT扫描Key words
middle route project of South-to-North Water Transfer/ expansive soil/ fissure-plane/ shear strength/ computerized tomography.分类
数理科学引用本文复制引用
胡波,龚壁卫,程展林..南阳膨胀土裂隙面强度试验研究[J].岩土力学,2012,33(10):2942-2946,5.基金项目
"十一五"国家科技支撑计划项目"南水北调工程若干关键技术问题研究与应用"之课题"膨胀土地段渠道破坏机理及处理技术研究"(No.2006BAB04A10) （No.2006BAB04A10）
国家自然科学基金资助(No.51008035,No.51108042). （No.51008035,No.51108042）
