مطالعه عددی سه‌بعدی پایداری شیب ماسه‌ای مسلح با ستون سنگی مسلح با ژئوگرید

نوع مقاله : مقاله پژوهشی

نویسندگان

1 عضو هیات علمی/دانشگاه رازی

2 دانشگاه رازی

چکیده

یکی از روش‌های مناسب و مؤثر برای مسلح کردن شیب‌های خاکی استفاده از ستون‌های سنگی با پوشش ژئوگرید می‌باشد، که این غلاف ژئوگرید به خوبی قادر است ظرفیت باربری شیب را افزایش و میزان نشست را در آن کاهش ِ دهد. هدف از انجام این پژوهش، مطالعه عددی رفتار ستون سنگی مسلح با پوشش ژئوگرید در پایدارسازی شیب خاکی ماسه‌ای به صورت سه بعدی در حالات مختلف است. نتایج حاصل از تحلیل به کمک نرم افزار تفاضل محدود FLAC3D نشان داده ِ است که ستون سنگی مسلح با پوشش ژئوگرید در شیب ماسه ِ ای اشباع، پایداری آن را تا حد رضایت بخشی نسبت به حالت شیب مسلح با ستون سنگی معمولی بهبود می‌بخشد. در این پژوهش پارامترهای مختلفی از جمله قطر ستون سنگی، سختی، چسبندگی و اصطکاک فنر کوپل ژئوگرید، فاصله مرکز به مرکز ستون‌های سنگی (نسبت S/D   )،و نحوه آرایش مسلح کننده‌ها بررسی شده‌اند. نتایج حاکی از آن است که پارامتر تأثیر گذار در ژئوگرید به منظور مسلح کردن ستون سنگی، چسبندگی فنر کوپل است، که با افزایش این پارامتر ظرافیت باربری شیب مسلح به صورت خطی افزایش می ِیابد (این بدان معنی است که استفاده از ستون سنگی مسلح با پوشش ژئوگرید، میتواند ظرفیت باربری شیب را بسته ِ به نوع مشخصات ژئوگرید، تا 1/8 برابر شیب مسلح با ستون سنگی معمولی بهبود بخشد). در حالت شیب مسلح با ردیف ً به معنای ستون سنگی بیشترین افزایش ظرفیت باربری در حالت = S/D    2 به وجود می‌آید، اما کاهش نسبت S/D الزاما افزایش چشمگیر ظرفیت باربری شیب نخواهد بود

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

3D Numerical Stability Investigation of Sand Slope Reinforced Using Geogrid Encased Stone Column

نویسندگان [English]

  • Mohammad Hajiazizi 1
  • Masoud Nasiri 2
1 Civil Engineering, Razi University, Kermanshah, Iran
2 Razi University
چکیده [English]

One of the efficient ways for reinforcing the earth’s slope is Geogrid Encased Stone Column (GESC). This technique can increase bearing capacity and decrease the settlement rate of the slope. The goal of this study is to perform a three-dimensional finite-difference numerical study on the behavior of GESC in the stabilization of sand slope. According to the results of the three-dimensional finite-difference analysis, the existence of GESC in the middle of the sand slope, as the optimal location for stone column placement, increased stability to an ideal level compared with the ordinary stone column (OSC). Different parameters including stone column diameter, coupling spring cohesion, coupling spring friction, center to center distance of columns (S/D ratio), and the layout of encasements were evaluated and discussed in this paper. The results indicated that the efficient parameter in geogrid is coupling spring cohesion; in which by increasing this parameter, slope bearing capacity increased linearly (i.e. the bearing capacity of slope reinforced using GESC could enhance up to 1.8 times of slope reinforced using OSC). In the case of row stone implementation, the maximum bearing capacity was that of S/D=2. However, a decrease in the S/D ratio did not necessarily increase the bearing capacity of slopes.

کلیدواژه‌ها [English]

  • Sandy Slope
  • Stone Column
  • Geogrid
  • Reinforcement
  • Numerical investigation

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نشریه مهندسی عمران امیرکبیر
دوره 52، شماره 3
خرداد 1399
صفحه 531-550

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