压实Q_3马兰黄土蠕变规律研究  

Research on the Creep Behavior of Compacted Q_3 Ma-Lan Loess

作　　者：朱才辉[1] 李宁[1] 刘俊平[1] 

机构地区：[1]西安理工大学岩土工程研究所,陕西西安710048

出　　处：《西安理工大学学报》2011年第4期392-399,共8页Journal of Xi'an University of Technology

基　　金：国家自然科学基金资助项目(50479023);高等学校博士点学科基金资助项目(20040700001)

摘　　要：为了研究压实Q3马兰黄土的蠕变特性,开展不同压实度、不同含水量下压实土的单轴排水与不排水蠕变试验,得到其轴向应变-应力-时间关系,采用已有的经验模型及H-K、Burgers、M-B元件模型分别描述其蠕变规律并对比分析其适宜性,采用能综合反映蠕变特性参数的等效蠕变模量E(t)来分析不同因素对蠕变规律敏感性。研究结果表明:Q3马兰黄土的蠕变特性对含水量敏感程度较大,对压实度次之,排水条件对低含水量和低压实度土体的蠕变特性敏感程度较大;采用M-B元件模型能够较准确地描述其瞬时弹性应变、衰减蠕变和稳定粘滞流动三个阶段,通过等效蠕变模量E(t)能够较好地反映不同初始条件下的蠕变效应,得到了E(t)与含水量w和轴向荷载σ0的经验公式。In order to study the creep behavior of compacted Q3 Ma-Lan loess,the axial creep tests under different drainage condition,compacted degree and moisture content are performed by high pressure oedometer test system,and the laws of stress-strain-time relationships are obtained.The empirical and component models and H-K、Burgers and M-B element models are used to depict the creep behaviors,and the feasibility of these models are analyzed too.The equivalent elastic modulus E（t） is adopted to analyze the creep sensibility of different factors.The results obtained from research show that the moisture content is sensitive to creeping effect more than compacted degree and the low moisture content with high compacted degree under different drainage conditions are largely sensitive to the creep behaviors.The adoptation of M-B element model is able to describe the instance elastic strain,attenuation creep and stable sticking flow of three stages.The equivalent elastic modulus E（t） is able to reflect the creep effect under the different initial conditions,whereby obtaining the empirical formula of E（t）,water contents w and axial loading σ0.

关 键 词：压实Q3马兰黄土 单轴压缩蠕变试验 应力-应变-时间关系 含水量 压实度 M-B蠕变模型 等效蠕变模量 

分 类 号：TU45[建筑科学—岩土工程]