含水率及压实度对压实黄土状粉土力学特性的影响  

Effects of water content and compaction degree on mechanical characteristics of compacted silty soil

作　　者：董山 王宏宇 李婕[1] 马富丽[1] 白晓红[1,2] DONG Shan;WANG Hong-yu;LI Jie;MA Fu-li;BAI Xiao-hong(College of Civil Engineering, Taiyuan University of Technology, Taiyuan 030024, China;Shanxi Key Laboratory of Geotechnical and Underground Engineering, Taiyuan 030024, China)

机构地区：[1]太原理工大学土木工程学院,山西太原030024 [2]岩土与地下工程山西省重点实验室,山西太原030024

出　　处：《广西大学学报（自然科学版）》2020年第5期978-985,共8页Journal of Guangxi University（Natural Science Edition）

基　　金：国家自然科学基金资助项目(51178287);山西省研究生创新项目(2018BY055)。

摘　　要：为了研究含水率和压实度对压实黄土状粉土变形与抗剪强度特性的影响,对不同含水率和压实度下的压实黄土状粉土开展了室内三轴压缩试验,得到了土体的应力—应变关系曲线及抗剪强度指标,并讨论了含水率和压实度对压实黄土状粉土应力—应变关系、粘聚力及内摩擦角的影响。试验分析结果表明:压实黄土状粉土的应力—应变关系随含水率的增大由应变软化型向应变硬化型转变;而随压实度的增大则是由弱硬化型转变为软化型。压实黄土状粉土的粘聚力随含水率的增大先增大后减小并在最优含水率附近取得最大值,内摩擦角则随含水率的增大而减小;随着压实度的增大,其粘聚力及内摩擦角均呈现增大的趋势。含水率及压实度对粘聚力的影响大于对内摩擦角的影响。To study the effects of water content and compaction degree on the characteristics of deformation and shear strength of compacted silty soil,a series of triaxial compression tests were conducted to compacted silty soil under different water contents and compaction degrees.Stress-strain curves and shear strength indexes of soil mass are obtained,their influences on stress-strain relation,cohesion and internal friction angle of compacted silty soil are discussed.The testing and analyzing results show that the stress-strain relation of compacted silty soil changes from strain softening to strain hardening with the increase of water content,while changing from weak strain hardening to strain softening with the increase of compaction degree.The soil cohesion increases first and then decreases with the increase of water content,reaching the peak value around the optimum water content,while the internal friction angle decreases with increasing water content.Both cohesion and internal friction angle of compacted silty soil increase with the increase of compaction degree.The influence of water content and compaction degree on cohesion is more obvious than that on internal friction angle.

关 键 词：压实黄土状粉土 含水率 压实度 应力—应变关系 粘聚力 内摩擦角 

分 类 号：TU411.7[建筑科学—岩土工程]