摘要
针对宁夏次生黄土含砂率大、透水性强的特点,以次生黄土为研究对象,以饱和度、压实度、膨润土掺量、含砂率为因素,应用ZJ型电动直剪仪和GZQ-1型全自动气压固结仪,设计正交试验方案L_(16)(4~5),设置35%、55%、75%和95%等4个饱和度水平,0.86、0.90、0.94和0.98等4个压实度水平,0、1.5%、3.0%和4.5%等4个膨润土掺量水平,15%、20%、25%和30%等4个砂土含量水平,研究了膨润土改性次生黄土的强度和压缩性,分析了各因素的作用规律及显著性,给出了最优组合。结果表明:压实度对次生黄土力学性能的改善有利,且影响显著;膨润土掺量对黏聚力的影响显著,对摩擦角和压缩性的影响不显著;粗砂含量为25%时对压缩性最为不利。增大压实度是改善次生黄土力学性能的有效措施,掺加膨润土不会对其力学性能产生显著的不利影响。
Aiming at the characteristics of high sediment concentration and water per^neability in secondar^^loess of Ningxia,taking the secondary^loess as the research object,the saturation degree,compaction degree,bentonite content and sand content as the factors,using the ZJ type electric straight shear and GZQ-1 type automatic pressure consolidation instrument,we designed orthogonal test program L,6(4 5).Saturation degree was set at 35%,55%,75%and 95%,compaction degree at 0.8 6,0.9 0,0.94 and 0.9 8,the contents of bentonite at 0,1.5%,3.0%and 4.5%,the sand content at 15%,20%,25%and 30%,respectively.The strength and compressibility of secondary loess modified by bentonite were studied.The effect and significance of each factor were analyzed and the optimal combination was given.The results show that the compaction degree is beneficial to the improvement of mechanical properties of secondary loess and the effect is significant.The effect of bentonite content on the cohesion is significant,but the effect on the friction angle and compressibility is not significant.When secondary loess of coarse sand content is 25%,compression is the most adverse.Increasing compaction is an effective measure to improve the mechanical properties of secondar^^loess.The incorporation of bentonite does not have a significant adverse effect on its mechanical properties.
作者
张鹏
杨瑞雪
崔自治
郄玥颖
康龙
ZHANG Peng;YANG Ruixue;CUI Zizhi;QIE Yueying;KANG Long(School of Civil Engineering and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China)
出处
《人民黄河》
CAS
北大核心
2018年第9期144-147,共4页
Yellow River
基金
国家大学生创新训练项目(201610749025)
关键词
膨润土
含砂率
力学性能
正交试验
次生黄土
bentonite
sand ratio
mechanical property
orthogonal test
secondary loess