بررسی مقاومت برشی فصل مشترک خاک رس-ژئوتکستایل با استفاده از الیاف ضایعات BCF

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه ژئوتکنیک، دانشکده مهندسی عمران، دانشگاه یزد، یزد، ایران

2 هیئت علمی

چکیده

با قرار دادن عناصر مسلح‌کننده مقاومت برشی خاک بهبود می‌یابد. پژوهش‌های متعددی در زمینه‌ی تسلیح خاک‌های درشت‌دانه انجام شده و کمتر به خاک‌های ریزدانه پرداخته شده است. بر اساس پژوهش‌های موجود مقاومت خاک ریزدانه - ژئوسنتتیک در مقایسه با خاک‌های درشت‌دانه ضعیف‌تر بوده و لازم است تا اندرکنش خاک‌های ریزدانه- مسلح کننده تقویت گردد. در این پژوهش از نمونه خاک رس حاوی حدود 80 درصد ریزدانه عبوری از الک 200 #و دو نوع ژئوتکستایل بدون بافت استفاده شد. مقاومت برشی خاک در اثر افزودن الیاف ضایعات نخ پلیپروپیلن با 2/0 ،7/0 و 2/1 درصد نسبت به وزن خشک خاک مورد توجه قرار گرفت. مقاومت برشی خاک-ژئوتکستایل با استفاده از دستگاه برش مستقیم بزرگ مقیاس تعیین شد، پاره ای از این آزمایش‌ها با بارگذاری – باربرداری خاک به اجرا درآمدند. نتایج آزمایش نشان داد که بارگذاری - باربرداری، مقاومت برشی را افزایش می‌دهد. افزودن 7/0 %الیاف به خاک مقاومت برشی فصل مشترک خاک - ژئوتکستایل را تا 15 درصد در شرایط بارگذاری – بدون باربرداری و تا 9 درصد در شرایط بارگذاری – باربرداری فزونی داده است. همچنین بارگذاری قائم بیشتر، استفاده از ژئوتکستایل با استحکام کششی بالاتر و کاهش رطوبت خاک از عوامل بهبود مقاومت برشی خاک- ژئوتکستایل در این مطالعه هستند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of Shear Strength of Clay Soil – Geotextile by Adding the BCF Waste Fibers

نویسنده [English]

  • bahareh ebrahimi alavijeh 1
1 Geotechnical engineering, Civil engineering, Yazd university, Yazd, Iran
2 ACADEMIC MEMBER
چکیده [English]

By placing the reinforcing elements, the shear strength of the soil improves. Several studies have been carried out on reinforcing of coarse grained soils, and less has been done on finegrained soils. Researches show that the shear strength of fine grained soil-geosynthetics is weaker than the coarse soils and should be to improve soil interaction with reinforcing elements. In this research, soil with about 80% passing the No.200 sieve and two types of non-woven geotextiles have been used. Shear strength of soil was considered by adding BCF waste polypropylene fibers with 0.2%, 0.7% and 1.2% by weight of dry soil. Shear strength of soil–geotextile determined by large direct shear machine and several tests were done in vertical loading–reloading conditions. Experimental results showed that vertical loading– reloading conditions increase interface shear strength. Addition of 0.7% fibers increase interface shear strength up to 15% and 9% in usual loading and loading-reloading conditions, respectively. Also increasing of normal stress in loading step, application of geotextile with higher tensile strength and reduction of moisture content are the factors improving shear strength of soil-geotextile in this study.

کلیدواژه‌ها [English]

  • Clay soil-geotextile interaction
  • Large scale direct shear test
  • Fibrous clay
  • Moisture
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