摘要
为探究酸污染对黄土物理性质的影响,采用浓度为0.5,1.0,2.0,3.0,4.0,6.0,8.0,10.0 mol/L的盐酸溶液浸泡离石黄土,制备酸污染试样,并以蒸馏水浸泡样作为对照组。通过室内试验探究酸污染离石黄土土粒相对密度、孔隙比以及塑性指数变化规律,并对酸污染离石黄土试样进行微观结构分析,进一步揭示离石黄土物理特性变化机理。试验结果表明:①离石黄土相对密度从2.73降至2.69,呈线性渐进减少;②酸浓度的增加导致试样孔隙比逐渐增大,离石黄土孔隙比从0.77增至1.33,呈单指数增长;③随酸浓度的增加,试样塑性指数从11.89增至13.73再降至7.34,呈现出先增大后减小的情形;④经酸污染作用后,离石黄土微观结构发生明显变化,即酸浓度越大,土体颗粒表面变得越粗糙,骨架颗粒越松散,细粒含量逐渐减小,孔隙面积不断增加。
The purpose of this research is to investigate the influence of acid pollution on the physical properties of loess.We prepared acid-contaminated loess specimens by immersing Lishi formation loess into hydrochloric acid solutions(concentrations of 0.5,1,2,3,4,6,8,10 mol/L),and also prepared distilled water-immersed specimens as the control group.Through laboratory tests on the variations of specific gravity,void ratio and plasticity index of acid-contaminated Lishi loess as well as micro-structure analysis,we revealed the variation mechanism of physical properties of Lishi loess.Results demonstrated that:1)the specific gravity of loess declined from 2.73 to 2.69,presenting a linear progressive reduction;2)the increase of acid concentration led to a gradual increase in the void ratio of specimens from 0.77 to 1.33,showing a single exponential growth;3)with the increase of acid concentration,the plasticity index of specimens augmented from 11.89 to 13.73 and then reduced to 7.34;4)after acid action,the microstructure of Lishi loess changed remarkably.With the increase of acid concentration,the surface of soil particles was rougher;the skeleton particle looser;fine particle content smaller and pore area larger.
作者
王念秦
鲁兴生
马啸
WANG Nian-qin;LU Xing-sheng;MA Xiao(College of Geology and Environment, Xi’an University of Science & Technology, Xi’an 710054, China;Shaanxi Key Laboratory of Geological Guarantee for Green Coal Development, Xi’an University of Science & Technology, Xi’an 710054, China)
出处
《长江科学院院报》
CSCD
北大核心
2020年第7期105-108,114,共5页
Journal of Changjiang River Scientific Research Institute
基金
国家自然科学基金项目(41572287)
陕西省科技统筹创新工程计划项目(2016KTCL03-19)。
关键词
离石黄土
酸污染
物理特性
塑性指数
微观结构
Lishi loess
acid corrosion pollution
physical characteristics
plasticity index
microstructure
