摘要
鄂东南通城地区分布着红色和白色两类花岗岩残积土,其物理力学特性存在明显的差异。以通城地区所选取的两类花岗岩残积土为研究对象,通过开展土工试验、X射线衍射试验和三轴剪切等相关试验,对比研究了两类花岗岩残积土的物理力学性质、矿物组成、固结压缩性和抗剪强度特性等。结果表明:红色花岗岩残积土细粒组分含量相对较高,为含砂黏土,白色花岗岩残积土为粉土质砂砾;两类花岗岩残积土的矿物成分均以石英、长石、云母和高岭石等为主,而红色花岗岩残积土中高岭石的含量相对更高;红色花岗岩残积土的应力-应变关系曲线形态随围压的变化存在转型现象,其固结变化体积随含水率的增加而增大,但红色花岗岩残积土的固结变形偏大,路基边坡填土时可优先选用白色花岗岩残积土,以降低路面沉降;两类花岗岩残积土的抗剪强度参数c、?值与含水率呈负相关关系,红色花岗岩残积土的抗剪强度高于白色花岗岩残积土,且水对红色花岗岩残积土的影响更为明显,因此在进行路基边坡填土时可选用低含水率的红色花岗岩残积土,以提高边坡的工程安全性。
Red and white granite residual soils are widely distributed in Tongcheng County of southeast Hubei Province of China.There are some differences in their physical and mechanical characteristics.This paper takes two types of granite residual soil selected in Tongcheng County as the research object,and conducts related experiments on physical and mechanical properties,mineral composition,consolidation compressibility and shear strength of the two types of granite residual soil through geotechnical test,X-ray diffraction test and triaxial shear test.The results indicate that the red granite residual soil with higher fine-grained particles is sandy clay and the white granite residual soil is silty gravel.The mineral composition of residual soil is mainly quartz,feldspar,mica and kaolinite,and red granite residual soil contains more kaolinite than white granite residual soil does.The shape of stress-strain curve of red granite residual soil changes with confining pressure.Though the consolidation volume of both types of soil increases with the increase of moisture content,the consolidation deformation of red granite residual soil is larger than that of white granite residual soil.White granite residual soil is preferred during subgrade filling so as to reduce the settlement of road surface.The shear strength parameters c and ? both have negative correlation with moisture content and the parameter of red granite residual soil is higher than that of white granite soil,and thus red granite residual soil with low moisture content can improve the engineering safety of the slope.
作者
戴航
晏鄂川
谭延嗣
柳万里
DAI Hang;YAN E'Chuan;TAN Yansi;LIU Wanli(Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China)
出处
《安全与环境工程》
CAS
北大核心
2020年第2期132-139,148,共9页
Safety and Environmental Engineering
基金
国家自然科学基金项目(41672313)。
关键词
花岗岩残积土
物理力学特性
矿物成分
抗剪强度
应力-应变曲线
工程安全性
granite residual soil
physical and mechanical characteristics
mineral composition
shear strength
stress-strain curve
engineering safety
