摘要
为了研究饱和黄土的动力非线性特征及其主要影响因素,通过选取黄土高原的不同场地,在室内动三轴试验的基础上,采用非线性拟合计算的方法得到饱和黄土的动剪切模量比和阻尼比,研究不同地区饱和黄土的动剪切模量比和阻尼比变化特征,分析饱和黄土动剪切模量比和阻尼比的区域差异性,探讨饱和黄土与原状黄土的动剪切模量比和阻尼比的差别,并研究物性指标对饱和黄土动力特性拟合参数的影响规律。研究结果表明:饱和黄土的动剪切模量比和阻尼比符合Hardin-Drnevich模型。区域分布特征对饱和黄土的动剪切模量比影响较小,对阻尼比影响显著。相比于原状黄土,饱和黄土的动剪切模量比均明显减小,由于区域分布导致的动剪切模量比离散性减小;而相同地区饱和黄土的阻尼比较原状黄土的阻尼比显著增大,且受黄土结构性差异的影响明显。初始孔隙比对饱和黄土的最大动剪切模量影响较大,而黏粒含量增加导致的结构性变化是造成饱和黄土最大剪应力幅值和最大阻尼比变化的主要原因。
In order to investigate the dynamic behaviors and influence factors of saturated loess,a series of dynamic triaxial tests were conducted to analyze the dynamic shear modulus and damping ratio of the loess sampled from 11 different sites in Loess Plateau,and the dynamic shear modulus ratio and the damping ratio were obtained by fitting the test results.The regional differences of the dynamic shear modulus ratio and damping ratio of saturated loess were discussed,and the differences of the dynamic shear modulus ratio and the damping ratio between the saturated loess and the original loess were also analyzed.In addition,influence of physical indexes on fitting parameters of the dynamic modulus and the damping ratio of the saturated loess was analyzed.The results indicate that the dynamic constitutive relation of the saturated loess obeys the Hardin-Drnevich model.The regional distributive characteristics of the loess have a significant influence on the damping ratio while slight on the dynamic shear modulus ratio.Both the value and the regional discreteness of the dynamic shear modulus ratio of the saturated loess are much smaller than those of the original loess.In the same site,however,the damping ratio of the saturated loess is markedly larger than that of the original loess,which is influenced by the loess structure.The maximum dynamic shear modulus of the saturated loess is greatly influenced by the initial void ratio,and the changes of the ultimate dynamic shear stress amplitude and the maximum damping ratio are mainly caused by the variation of structural characteristics of the loess resulted from the increase of the clay content.
作者
王谦
马金莲
马海萍
王峻
王兰民
高中南
钟秀梅
WANG Qian;MA Jinlian;MA Haiping;WANG Jun;WANG Lanmin;GAO Zhongnan;ZHONG Xiumei(Key Laboratory of Loess Earthquake Engineering,China Earthquake Administration and Gansu Province,Lanzhou,Gansu 730000,China;Lanzhou Institute of Seismology,China Earthquake Administration,Lanzhou,Gansu 730000,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2019年第9期1919-1927,共9页
Chinese Journal of Rock Mechanics and Engineering
基金
中国地震局地震预测研究所基本科研业务经费项目(2018IESLZ06)
国家自然科学基金资助项目(51778590)
兰州市科技计划项目(2018–1–123)~~
关键词
土力学
最大动剪切模量
动剪切模量比
阻尼比
动三轴试验
区域差异性
soil mechanics
maximum dynamic shear modulus
dynamic shear modulus ratio
damping ratio
dynamic triaxial test
regional difference
作者简介
谦(1985–),男,2008年毕业于兰州理工大学金属材料工程专业,现任副研究员、硕士生导师,主要从事黄土动力学与地震工程理论与试验方面的研究工作。E-mail:wangq0930@126.com;通讯作者:钟秀梅(1981–),女,现任副研究员。E-mail:xmzhong26@163.com
