摘要
对一定试验含水率及干密度下具有不同结构性(排列)的压实黄土试样进行侧限压缩试验,分析制样含水率引起的结构性变化对不同试验含水率压实黄土侧限压缩特性的影响,探讨压缩性指标与初始结构性参数之间的关系。以饱和压实黄土的压缩曲线为基础,通过引入反映结构性影响的初始结构性参数,提出压实黄土压缩曲线的表达式,根据此表达式可以确定湿载耦合时压实黄土的压缩变形。研究结果表明:制样含水率引起的结构性变化对压实黄土的侧限压缩特性有一定的影响,影响程度随试验含水率增大而减小,对饱和压实黄土压缩特性几乎没有影响;压实土的初始结构性随制样含水率的增大或试验含水率的减小而增强,弹性指数基本上不受结构性的影响,结构屈服压力及压缩指数皆随初始结构性参数增大而增大。在不同的试验含水率及制样含水率下,压缩指数及结构屈服压力与初始结构性参数之间皆有良好的归一化非线性关系,且可用以饱和压实黄土的压缩性指标为参照状态的双曲线来描述。
A series of confined compression tests were performed on compacted loess samples of different structures（fabrics） with the same dry density and initial testing water content. The influence of structure caused by different molding water contents on the compressive properties was analyzed for compacted loess with different initial testing water contents. The relationships between the compressibility indices and the initial structural parameter were investigated. The compression curve of saturated compacted loess was regarded as the reference state. The formula of compression curve of unsaturated compacted loess was established to determine the compressive deformation under the coupling of moisture and stress. The test results show that the molding water content has certain influence on the confining compression characteristic of compacted loess,and the extent of the influence decreases with the increase of initial testing water content. The structural influence on compressive deformation of saturated compacted loess is little. The initial structure index of compacted loess increases with increasing of molding water content or decreasing of initial testing water content. The structural change has little influence on the elastic compression indices,but both the structural yield stress and compression indices increase with the increase of initial structural parameter. The relationships of the structural yield stress and the compression indices with the initial structural parameter are normalized well and can be described with hyperbola under different initial testing water contents and molding water contents.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2014年第9期1939-1944,共6页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(50878183)
陕西省教育厅省级重点实验室重点科研资助项目(2010JS086)
西安理工大学2012年度特色研究计划项目(118–211302)
关键词
土力学
压实黄土
侧限压缩试验
制样含水率
初始结构性参数
压缩性指标
soil mechanics
compacted loess
confined compression test
molding water content
initial structural parameter
compression indices
