اثر آلاینده های نفتی بر خاصیت واگرایی و مقاومت برشی خاک های رسی واگرا

نوع مقاله : مقاله پژوهشی

نویسندگان

دانشکده فنی، دانشگاه بین المللی امام خمینی (ره،) قروین، ایران

چکیده

خاک‌های رسی واگرا خاک‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌هایی هستند که دارای درصد زیادی یون سدیم می‌باشند. این خاک‌ها وقتی در معرض تراوش آب قرار می‌گیرند مستعد شسته شدن و فرسایش هستند. در این پژوهش تاثیر نفت خام به عنوان یک اثر جنبی آلودگی (احتمالا مثبت) بر میزان واگرایی خاک پرداخته می‌شود. بدین منظور ابتدا خاک به صورت مصنوعی با اضافه نمودن محلول هگزامتافسفات سدیم واگرا گردیده و سپس تعدادی آزمایش پین هول بر روی نمونه‌های خاک واگرا شده با مقادیر مختلف نفت خام (1، 3، 5 و 7 درصد) انجام گردید. علاوه بر این، اثر آلاینده نفت خام بر روی مقاومت برشی خاک به کمک آزمایش تک محوری انجام شد. نتایج بدست آمده نشان داد که با حضور نفت و افزایش درصد آن و زمان تماس نفت و خاک، واگرایی خاک کاهش می‌یابد بدین صورت که با افزایش تدریجی نفت، خاک کاملا واگرا به خاک غیر واگرا تبدیل شد. همچنین آزمایش‌های تک محوری نشان داد که ابتدا مقاومت نمونه‌ها تا مقدار نفت 3% افزایش می‌یابد و مقادیر نفت بیشتر باعث کاهش مقاومت خاک شدند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Oil Contaminats Effect on the Dispersivity Potential and Shear Strength of Dispersive Clay Soils

نویسندگان [English]

  • M. Hasanloorad
  • H. Khabbazi
چکیده [English]

Basic Divergent clay soils are soils that have high percentage of sodium ions.The soils prone to leaching when placed under water seepage and erosion. In this research, the impact of crude oil as a side effect of pollution (possibly positive) on the amount of divergence of the soil will be discussed. Therefore, first soil artificially by adding a solution of sodium hexametaphosphate were divergent and then some pinhole test on soil samples with different amounts of crude oil diverged (1, 3, 5 and 7%) were performed. In addition to this, the effect of crude oil pollutants on the shear strength and uniaxial testing was conducted to help. Results obtained showed that with presence of oil and increase in percentage of oil and the time of soil and oil contact, dispersivity of soil decrease. Thus with gradual increase of oil, the territory is quite divergent soil became non-divergent. Also the,single pivot (uniaxial )tests experiments showed that at the first samples strengths increase to 3% oil content and more oil quantities reduces the the resistance of the soil.

کلیدواژه‌ها [English]

  • Clay Soils
  • Dispersivity
  • Crude Oil
  • Pinhole Test
  • uniaxial test
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