土工基础

土工基础 ›› 2021, Vol. 35 ›› Issue (6): 759-763.

• 专题论述 • 上一篇    下一篇

不同浓度CuSO4污染黏性土力学特性研究

王小平1，吴 炎1，谢丽文1，索巧巧1，高海飞1，胡 坤2   

  1. （1．常州大学怀德学院，江苏靖江 214500，2．常州大学环境与安全工程学院，江苏常州 213164）
  • 收稿日期:2021-10-25 修回日期:2021-10-31 出版日期:2021-12-30 发布日期:2021-12-24
  • 作者简介:王小平（1978-），男，博士，讲师，研究方向为环境岩土工程。
  • 基金资助:
    深部岩土力学与地下工程国家重点实验室开放基金（SKLGDUEK1704）；泰州市科技支撑计划项目（SSF20210062）

Experimental Study on Mechanics Properties of Clay Polluted with Different Concentrations of CuSO4

WANG Xiaoping1, WU Yan1, XIE Liwen1, SUO Qiaoqiao1, GAO Haifei1， HU Kun2   

  1. (1.Huaide College, Changzhou University, Jingjiang, 214500；
    2.School of Environmental and Safety Engineering, Changzhou University, Changzhou, 213164)
  • Received:2021-10-25 Revised:2021-10-31 Online:2021-12-30 Published:2021-12-24

摘要： 为研究重金属离子的入侵对土体工程特性的影响，选取江苏靖江市的典型黏性土层，通过配置0%、0.5%、1%、2%、3%这5种浓度的CuSO4溶液，采用直剪试验、三轴试验、无侧限抗压强度、压缩试验来探究CuSO4污染土体前后力学性质的差异，并通过相应环境试验与XRD对结果进行分析，研究结果表明：直剪试验和三轴试验中土体的最小剪应力出现在CuSO4浓度为0.5%处，而无侧限抗压强度的最小值点出现在0.5%~1%CuSO4浓度范围。两个试验得出的黏聚力以及无侧限抗压强度都呈现先减小再增加的趋势，呈内“凹”型变化。黏聚力变化的极值点出现在0.5%处。三轴试验得出的内摩擦角呈下降变化规律，直剪试验值则振荡波动。呈酸性的CuSO4溶液会溶解土中的胶结物质，Cu2+会破坏原有的双电层结构，导致结合水膜变薄，强度降低。高浓度的CuSO4溶液则是单电层结构，并且产生胶体物质。


关键词: CuSO4污染, 黏土, 黏聚力, 环境特性

Abstract: In order to study the influence of heavy metal ions intrusion on the soil engineering properties, the typical clay layer in Jingjiang City of Jiangsu Province was selected. Soil samples with five concentrations of CuSO4 solutions (0%, 0.5%, 1%, 2% and 3%) were prepared. Direct shear test, triaxial test, unconfined compressive strength test and compression test were used to investigate the difference of mechanical properties before and after CuSO4  contaminated soil samples, and the corresponding environmental tests and X-Ray powder Diffraction (XRD) tests were used to compare the results The results show that the minimum shear strength of the soil sample appears at the concentration of 0.5% CuSO4  in direct shear test and triaxial test, and the minimum value of unconfined compressive strength appears in the concentration range of 0.5%~1% CuSO4 . The cohesion and unconfined compressive strength of the two tests decrease first and then increase, showing a “concave” type change. The extreme value of the cohesion change appears at 0.5%. The results of triaxial test show that the internal friction angle decreases, while the direct shear test value oscillates. The acidic CuSO4  solution would dissolve the cementitious substances in soil samples, and Cu2+ would destroy the original electric double layer structure, resulting in the thinning of the bound water film and the reduction of the strength. The CuSO4  solution with high concentration had a single electric layer structure and produces colloidal substances.


Key words: CuSO4 ,  , pollution, clay, cohesion, environmental properties

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