摘要
选取河南三门峡地区马兰黄土,掺加不同比例的膨润土与十六烷基三甲基溴化铵(HDTMA),开展界限含水率和标准击实试验,探讨膨润土-HDTMA对垃圾填埋场黄土衬里材料可施工性能的调控机理。研究表明:当膨润土的质量掺量超过10%时,黄土物理指标由粉土类过渡为黏土类;掺入质量掺量小于4%的HDTMA,有助于改善黄土的物理性质;此外,膨润土与HDTMA能够缓冲盐分对黄土衬里材料物理性质的消极影响。随着膨润土增加,改性黄土最大干密度和最优含水率分别增大和减小;HDTMA的掺入加剧了黄土最大干密度的减小趋势,但对最优含水率影响有限。从微观角度,HDTMA的掺入,改变了黏土颗粒层间结构;膨润土的掺入,导致包裹粗颗粒的黏土细颗粒占据了更多的空间。据此,建立了膨润土改性黄土最大干密度与最优含水率的线性函数关系。从可施工性角度而言,黄土作为垃圾填埋场衬里材料,膨润土掺量需不小于10%,HDTMA掺量建议不超过2%。
The tests for the limit moisture content and compaction on Malan loess from Sanmenxia in Henan mixed with different proportions of bentonite and HDTMA were conducted to explore the effect mechanism of bentonite and HDTMA on the workability of loess liners in landfills.The plasticity index of loess increased from silt to clay when the mass content of bentonite was more than 10%,and to mix HDTMA with a mass content less than 4%could optimize the physical properties of loess.Besides,both of the bentonite and HDTMA could buffer the negative effects of salts on physical properties of loess.The maximum dry density and optimal moisture content of the loess would respectively be increased and reduced with the increase of the bentonite content.The addition of HDTMA was benefit to reduce the maximum dry density of loess,but had a little influence on the optimal moisture content.In the microstructure,the HDTMA changed the structure of clay particles;the increase of bentonite made clay particles of being adhered to coarse particles occupy more spaces.Based on the data by tests,a linear function relation between the maximum dry density and the optimal moisture content for the modified loess was proposed.From the perspective of workability,the proportion of bentonite should be more than 10%and the proportion of HDTMA should be less than 2%in loess for liners of landfills.
作者
朱会强
张明
杜耀晨
张影
ZHU Huiqiang;ZHANG Ming;DU Yaochen;ZHANG Ying(Zhongyun International Engineering Co.,Ltd.,Zhengzhou 450000,China;Zhengzhou University of Aeronautics,Zhengzhou 450015,China)
出处
《工业建筑》
CSCD
北大核心
2021年第8期160-165,共6页
Industrial Construction
基金
国家自然科学基金项目(41902266)
河南省高等学校重点科研项目(21A410004)
河南省住房城乡建设科技计划项目(HNJS2020-k25)。
