复杂应力路径下粉土的动力特性研究  

Study on dynamic characteristics of silty soil under complex stress path

作　　者：赵津东 董金梅 沈震 陈凡 ZHAO Jindong;DONG Jinmei;SHEN Zhen;CHEN Fan(Institute of Geotechnical Engineering,Nanjing Tech University,Nanjing 210009,China)

机构地区：[1]南京工业大学岩土工程研究所,江苏南京210009

出　　处：《南京工业大学学报（自然科学版）》2020年第2期237-241,共5页Journal of Nanjing Tech University(Natural Science Edition)

摘　　要：为了解复杂应力路径下粉土的动力特性,以江苏苏北某地区粉土为研究对象,通过空心圆柱扭剪仪研究复杂应力路径下粉土的动力特性,得到粉土动模量和阻尼比随含水率、干密度、围压等的变化规律。结果表明:在相同动剪应变的情况下,含水率越高,动剪切模量越小;干密度和围压越高,动剪切模量越大。通过对动剪切模量的处理得到残余动剪切模量约为0.2Gmax。采用Hardin-Drnevich模型对轴向和剪切向骨干曲线进行拟合,得到了复杂应力路径下粉土的动力学参数,最大弹性模量、最大剪切模量和含水率、干密度、围压的线性关系,以及粉土动泊松比的变化范围。研究结果可为粉土地区的工程设计提供参考依据。In order to understand the dynamic characteristics of silt under a complex stress path, the dynamic characteristics of the silt in the northern Jiangsu province under a complex stress path were studied with a hollow cylinder torsion shear instrument. The rule that dynamic modulus and damping ratio would change with moisture content, density as well as confining pressure was obtained. Results showed that under the same dynamic shear strain, the higher the moisture content was, the smaller the dynamic shear modulus was, and the higher the dry density and confining pressure, the greater the dynamic shear modulus. By normalizing the dynamic shear modulus, the residual dynamic shear modulus was about 0.2Gmax. By using Hardin-Drnevich model to fit the axial and shear diaphysis curves, the obtained results were including the kinetic parameters of silt under the complex stress path, the linear relationship of the change of the maximum dynamic elastic & dynamic shear modulus with the moisture content, dry density as well as confining pressure and also the change range of silt dynamic poisson’s ration. The results could provide reference for the engineering design of silty land area.

关 键 词：粉土 动模量 含水率 干密度 围压 复杂应力路径 

分 类 号：U416.03[交通运输工程—道路与铁道工程]