بهبود خواص هیدرولیکی خاک رس کائولینیت با افزودن نانو رس

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد، دانشکده مهندسی عمران، دانشگاه یزد

2 استادیار، دانشکده مهندسی عمران، دانشگاه یزد

3 استادیار، دانشکده مهندسی عمران و محیط زیست، دانشگاه صنعتی امیرکبیر

چکیده

خاکهای رسی به علت ویژگی‌های خاصشان در اجرای پروژه‌های ژئوتکنیکی و زیست ‌محیطی مانند پرده‌های آب‌بند با نشت بسیار کم به طور وسیعی استفاده می‌شوند.
با پیشرفت فن‌آوری نانو، شاهد استفاده از نانو مواد به منظور بهبود ویژگی‌های مواد در بسیاری از شاخه‌های مهندسی از جمله مهندسی ژئوتکنیک هستیم. در مقاله حاضر، به بررسی آزمایشگاهی ویژگی‌های هیدرولیکی خاک رس کائولینیت با افزودن نانو‌‌رس پرداخته شد. مجموعه‌ای از آزمایش‌ها، شامل حدود آتربرگ، تراکم استاندارد، تحکیم یک بعدی و ظرفیت تبادل کاتیونی بر روی خاک رس کائولینیت معدن زنوز و مخلوط آن با درصد‌های مختلف نانو‌‌رس، انجام شد. بر پایه نتایج آزمایشگاهی، با افزودن 8% نانو‌‌رس به خاک رس کائولینیت دامنه خمیری و ضریب نفوذپذیری آن در مقایسه با خاک رس کائولینیت بترتیب 184% افزایش و 300 برابر کاهش
یافتند؛ همچنین نتایج آزمایش ظرفیت تبادل کاتیونی، افزایش این ظرفیت از 12 به meq/100gr 21 با افزودن 8% نانو‌‌رس را نشان داد. این افزایش به علت افزایش قابل توجه در مقدار یون سدیم موجود در نمونه است.

کلیدواژه‌ها


عنوان مقاله [English]

Improvement in the Hydraulic Properties of Kaolinite with Adding Nanoclay

نویسندگان [English]

  • zeinab fakhri 1
  • reza pourhosseini ardekani 2
  • taghi ebadi 3
1 M. Sc., Civil Engineering Department, Yazd University
2 Assistant professor, Civil Engineering Department, Yazd University
3 Assistant professor, Civil and environmental Engineering Department, AmirKabir University of Technology (AUT)
چکیده [English]

Due to special properties of clay, it has widely been used in geotechnical and geoenvironmental projects such as barriers in which very low seepage is required.
With advances in nanotechnology, we are witnessing of nanomaterials application to modify material properties in different branches of engineering such as geotechnical engineering. In this study, the hydraulic properties of Kaolinite extracted from Zenuz mine have been investigated experimentally by using nanoclay as an additive. A series of tests, comprising Atterberg limits, standard compaction, one dimensional consolidation and cation exchange capacity test, were conducted on Kaolinite and modified Kaolinite with 1%, 2%, 4%, and 8% nanoclay. According to experimental results, adding 8% nanoclay to Kaolinite increased plasticity index to 184%, and decreased the hydraulic conductivity 300 times when compared with raw Kaolinite. In addition, results of cation exchange capacity test showed that nanoclay caused an increase in cation exchange capacity from 12 to 21 meq/100 gr. This increase was related to a considerable increase in the amount of Na+.

کلیدواژه‌ها [English]

  • Nanoclay
  • Hydraulic conductivity
  • Kaolinite
  • One dimensional consolidation test
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