بررسی اثر آلاینده‌های آلی بر روی خصوصیات تحکیمی خاک‌های ریزدانه

نوع مقاله: مقاله پژوهشی

نویسندگان

گروه مهندسی آب، دانشکده مهندسی و فن‌آوری، دانشگاه تهران، ایران

چکیده

خصوصیات خاک‌های رسی در تماس با آلاینده‌های آلی کاملا دستخوش تغییر می‌گردد و پارامترهایی مانند نوع ماده آلاینده آلی و تاریخچه تنش خاک، کاملا در تعیین رفتار آن تاثیر‌گذار است. لذا در این پژوهش به بررسی خصوصیات تحکیم‌پذیری دو نوع خاک رسی با پلاستیسیته بالا و پایین پرداخته شده است. نمونه‎های خاک با استفاده از روش دوغابی و نمونه دوغابی فشرده شده تحت یک بار از پیش تعیین شده برای نشان دادن اثر تاریخچه تنش با آب و غلظت‌های مختلف (10، 25 و 40 %) از دو ماده آلی گلیسرول و اتانول تهیه گردید. نتایج نشان می‌دهد که شاخص فشردگی (cc) در شرایط اسلاری با افزایش غلظت ماده آلاینده افزایش می‌یابد. اما در مورد نمونه با تاریخچه تنش، کاهش شاخص فشردگی در نمونه‎های خاک وجود دارد. فشار پیش تحکیمی در مورد خاک با پلاستیسیته پایین با افزودن ماده آلاینده افزایش پیدا می‌کند، اما برای خاک‌هایی با پلاستیسیته بالا هیچ تغییر قابل توجهی به‌وجود نمی‌آید. به عبارت دیگر تغییرات شاخص فشردگی وابسته به نوع خاک و مواد شیمیایی آلاینده می‌باشد.
 

کلیدواژه‌ها


عنوان مقاله [English]

Investigation of the Effect of Organic Pollution on the Consolidation Behavior of Fine Soils

نویسندگان [English]

  • Iman Beytolahpour
  • Ali Raeesi Estabragh
Faculty of Soil and Water Engineering, University of Tehran, Iran
چکیده [English]

Clay soils characteristics are completely changed in the exposure of the organic pollution, and the soil behavior determination is completely affected by some parameters such as organic pollutant type and stress history. Therefore, the soil consolidation characteristics of two kinds of clay soil with low and high plasticity have been studied. The soil samples were prepared from slurry method and slurry samples were compressed under a pre-defined load to represent the effect of stress history and different concentrations (10, 25, and 40%) of glycerol and ethanol. The results represent that the compression index (Cc) increases with increasing the concentration of the pore fluid under the slurry conditions. However, compression index decreases in samples with stress history. Although the pre-consolidation pressure increases with increasing the pollutant concentration in the low plasticity soil, the same factor is not significantly affected by pollutant concentration in the high plasticity soil. In other words, the variation of compression index is dependent on the type of the soil and the chemical composition of pore fluid.
 

کلیدواژه‌ها [English]

  • Compression Index
  • Slurry Test
  • Clay Soil
  • Glycerol
  • Ethanol
[1]. Fretwell B. A., Burgess W. G., Jefferies N. L. and Dottridge J., “Distribution of volatile organic compounds in pore water of the seasonally unsaturated chalk aquifer,” In: Contaminated land and Ground water: Future directions. Geology Society, (ed. By Lerner, D.N. and Walton, N.R.G.). London, Engineering Geology Special publication, 14, pp. 219-226, 1998.##

[2]. Abdul A. S., Gipson T. C., and Rai D. N., “Laboratory studies of the flow of some organic solvents and their aqueous solution through bentonite and kaolinite clays,” Ground Water 28, pp. 524–530, 1990.##

[3]. Meegoda N. J. and Rajapakse R. A., “Short-term and long-term permeability of contaminated clay,” J. Environ. Eng. 119 (4), pp. 725–743, 1993.##

[4]. Al sanad H. A., and Ismael N. F., “Aging effect on oil contaminated Kuwaiti sand,” Journal of Geotechnical and Geoenvironmental Engineering, 123(3), pp. 290-294, 1997.##

[5]. USEPA, 1988, “Must for USTs A Summary of the New Regulations for the Underground Storage Tank Systems,” EPA/530/UST-88/008, Office of Underground Storage Tanks, U.S. Environmental Protection Agency, Washington, DC.##

[6]. Sridharan A., Nagaraj T. S. and Sivapullaiah P. V., “Heaving of soil due to acid contamination,” Proceeding 10th International Conference Soil Mechanics and Foundation Engineering, Stockholm Publication Committee 10th ICSMFE, Balkema, Rotterdam, Vol. 2, pp. 383-386, 1981.##

[7]. Moore C. A. and Mitchell J. K., “Electromagnetic forces and soil strength,” Geotechnique 24 (4), pp. 627–640, 1974.##

[8]. Daniel .E, Andersond C., and Boyntons S. “Fixedwall versus flexible-wall permeameters,” In Hydraulic barriers in soil and rock. American Society for Testing and Materials, Special Technical Publication No. 874, pp. 107-126, 1985.##

[9]. Meegoda N. J. and Ratnaweera P., “Compressibility of contaminated fine-grained soils,” Geotechnical Testing Journal, Vol.17, No.1, pp.101-112, 1994.##

[10]. Chen J., Anandarajah A. and Inyang H., “Pore fluid properties and compressibility of kaolinite,” Journal of Geotechnical and Geoenvironmental Engineering, Vol. 126, No. 9, pp. 798-807, 2000.##

[11]. Singh S. K., Srivastava R. K. and John S., “Settlement characteristics of clayey  soils contaminated with petroleum hydrocarbons.,” Soil & Sediment Contamination, Vol. 17, No. 3, pp. 290-300, 2008.##

[12]. Matteo L. D., Bigotti F. and Ricco R., “Compressibility of kaolinitic clay  contaminated by ethanol-gasoline blends,” Journal of Geotechnical and Geoenvironmental Engineering, Vol. 137, No. 9, pp. 846-849, 2011.##

[13]. Kermani M. and Ebadi T., “The effect of oil contamination on the geotechnical properties of fine-grained soils.,” Soil Sediment Contamination, Vol. 21, pp. 655-671, 2012.##

[14]. Khosravi E., Ghasemzadeh H., Sabour M. R. and Yazdani H., “Geotechnical properties of gas oil-contaminated kaolinite.” Engineering  Geology, Vol. 166, pp. 11-16, 2013.##

[15]. Ying W., Jiang F., Qianxin L., Xianguo L., Xiaoyu W., Guoping W., “Effects of crude oil contamination on soil physical and chemical properties in Momoge Wetland of China,” Chinese Geographical Science, 23(6): pp. 708–715, 2013.##

[16]. Ratnaweera P. and Meegoda J. N., “Shear strength and stressstrain behavior of contaminated soils” Geotech. Test. J. 24 (2), pp. 1–8, 2005.##

[17]. Fang H. Y. . “Introduction to environmental geotechnology,” CRC Press. FINE, 1997. Soil interactions with petroleum hydrocarbons: abiotic processes., Soil Technology, pp. 133-153, 1997.##