EXPERIMENTAL RESEARCH ON THE EFFECT OF THE HEAVY METAL POLLUTANTS ON SOIL COMPACTNESS AND SHEAR STRENGTH
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摘要: 通过在实际重金属冶炼企业的尾矿库、废料堆填区采取重金属尾矿样品,与代表性净土进行掺和,配制了不同压实度、不同龄期、不同掺和比的重金属污染土样;在各自的最优含水量下,进行击实和直接剪切等物理力学试验,研究重金属污染对土的压实特性与抗剪强度的影响规律。试验表明:1)重金属污染对土体击实特性的影响,金属Mn的影响不大,Pb、Zn、Cd、Cr影响较大,后者表现为随掺和比增大,最优含水量减小,土的最大干密度增大;2)随着重金属污染土体压实度的增大,土的黏聚力C逐渐增大的,内摩擦角值逐渐降低,污染土的强度指标明显低于重塑净土的抗剪强度指标;3)重金属污染的作用效应是一个缓慢的过程,随着重金属污染物作用时间的延长,土的黏聚力c值下降,内摩擦角值上升;4)随着污染浓度的增加,土的黏聚力c值增大,则值呈降低趋势。Abstract: The heavy metal tailing samples were taken from tailing pond and landfill site of wastes, which were then mixed with typical uncontaiminated soil.The heavy metal contaminated samples with different incorporation ratio, different density and ages were prepared.Under their respective optimum moisture content, direct shear test and the compaction test were done in order to study the effect rules of compaction and strength shear by heavy metal pollution.The results showed: 1) Heavy metal pollution affected the compaction characteristics of soil.Mn had a weak impact on the soil.Pb, Zn, Cd, and Cr had great impacts on the soil, the maximum dry density of soil increased, optimum moisture content decreased with the different incorporation ratio increasing;2) with the degree of consolidation increasing, cvalue gradually increased, value decreased;3) the diffusion effect on the mechanical characteristics of soil was a slow process, cvalue gradually decreased, and value increased with time;and 4) with the increasing of concentration of heavy metal, cvalue gradually increased, and value decreased.
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Key words:
- heavy metals /
- contaminated soil /
- compaction /
- shear strength /
- mechanism ?
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[2] 李妍.农田重金属污染触目惊心每年污染1200万 t 粮食[N].中国经济周刊,2011-2-22. 史江涛.重金属污染成环保治理重点[N].参考消息,2011-2-28(16). [3] Shin Eun Chul, Das B M. Bearing Capacity of Unsaturated OilContaminated Sand[C]∥ Proceedings of the International Offshore and Polar Engineering Conference.2000(2):368-373. [4] Ratnaweera P, Meegoda J N. Shear Strength and Stress-Strain Behavior of Contaminated Soils[J]. Geotechnical Testing Journal.2006,29(2):133-140. [5] Pachecoe Silva D, Esquivel E R, Giacheti H L, et al. Copper Chloride Contamination Influence on the Shear Strength of Soils, Tarauneh Used as Liners[J]. Solos e Rochas,2005,28(3):283-294. [6] Maaitah O N, Al-Hamaiedeh H D. Effect of Treated and Raw Wastewater on the Behavior of Unsaturated Soil[J]. Electronic Journal of Geotechnical Engineering.2005,10. [7] Singh S K, Srivastava R K, Siby J. Settlement Characteristics of Clayey Soils Contaminated with Petroleum Hydrocarbons[J]. Soil and Sediment Contamination,2008,17(3):290-300. [8] Meegoda N J, Rajapakse R A. Short-Term and Long-Term Permeabilities of Contaminated Clays[J]. Journal of Environmental Engineering,1993,119(4):725-743. [9] Rajasekaran G, Rao S N. Effect of Pollutants on the Physical and Engineering Behavior of Lime-Treated Marine Clay[J]. Marine Georesources and Geotechnology,2001,19(1):17-35. [10] 朱春鹏,刘汉龙.污染土的工程性质研究进展[J].岩土力学,2007,28(3):625-630. [11] 朱春鹏,刘汉龙,沈扬.酸碱污染土强度特性的室内试验研究[J].岩土工程学报,2011,33(7):1146-1152. [12] 朱春鹏,刘汉龙,张晓璐.酸碱污染土压缩特性的室内试验研究[J].岩土工程学报,2008,30(10):1477-1483. [13] 李琦,施斌,王有诚.造纸厂废碱液污染土的环境岩土工程研究[J].环境污染与防治,1999,19(5):16-18. [14] 李相然,姚志祥,曹振斌.济南典型地区地基土污染腐蚀性质变异研究[J].岩土力学,2004,25(8):1229-1233. [15] 谢荣秀,田大伦,方晰.湘潭锰矿废弃地土壤重金属污染及其评价[J].中南林学院学报,2005,25(2):38-41. [16] 钱家欢,殷宗泽.土工原理与计算[M].北京:中国水利水电出版社,1996:9-26.
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