بررسی عوامل مؤثر بر عملیات تراکم دینامیکی در خاک های دانه ای مبتنی بر روش فازی

نویسندگان

1 دانشگاه آزاد اسلامی واحد زنجان

2 دانشگاه آزاد اسلامی واحد علوم و تحقیقات تهران

چکیده

روش تراکم دینامیکی با پرتاب وزنه یکی از روش های بهسازی خاک است که با توجه به مزیت های آن نسبت به سایر روش های بهسازی خاک امروزه اقبال قابل توجهی نسبت به آن دیده می شود. در این مقاله تلاش شده است تا با استفاده از سیستم فازی و روش استنتاج سوگنو، تأثیر پارامترهای دخیل در عملیات بهسازی به روش تراکم دینامیکی بر روی عمق بهبود نسبی بررسی گردد. متغیرهای ورودی سیستم شامل وزن کوبه، ارتفاع کوبش، شعاع کوبه، فواصل کوبش، تعداد ضربات و مقاومت نفوذ مخروط خاک بوده و از چهار عمق بهبود نسبی به عنوان خروجی سیستم برای خاک های دانه ای سست بهره گرفته شده است. داده های ورودی سیستم از مقالات معتبر علمی استخراج شده است. پس از ایجاد مدل فازی، جهت صحه گذاری تحلیل فازی، نتایج حاصل با نتایج عملیات تراکم دینامیکی معتبر جهان معتبرسازی گردیده و سپس به صورت مطالعه موردی، تراکم دینامیکی انجام گرفته در بندر شهید رجایی ایران با استفاده از مدل فازی تهیه شده، تحلیل شده است. نتایج به دست آمده نشان می دهد که اثرات وزن کوبه بیشتر از ارتفاع کوبش بوده و کاهش فواصل کوبش در درجه سوم اهمیت قرار دارد. همچنین اندرکنش وزن کوبه و ارتفاع کوبش، بیشترین نقش را در روش های طراحی ایفا می کند. مطالعات نشان می دهد که شعاع بهینه کوبه برای اغلب الگوهای کوبش با انرژی های اعمالی متوسط به بالا برابر 1.5 تا 2 متر، تعداد ضربات بهینه کوبش برابر 25 ضربه و فاصله کوبش بهینه برابر 6 الی 7 متر می باشد و استفاده از این الگوی کوبش سبب به دست آمدن بیشترین عمق بهبود می گردد.

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation of Influential Factors on the Dynamic Compaction Operation of Granular Soils Based on Fuzzy Method

نویسندگان [English]

  • Hamid Koohsari 1
  • Asadollah Najafi 1
  • Hamid Alielahi 1
  • Mohammad Adampira 2
چکیده [English]

Dynamic compaction (DC) technique with tamping is one of the soil improvement methods. Nowadays, there is a considerable interest in DC due to its advantages among the methods of soil improvement. In the present study, fuzzy logic and Sugeno inference system have been used to evaluate the influence of parameters involved in dynamic compaction over the depth of improvement. Input variables are used for loose granular soils and include tamper weight, height of tamping, tamper radius, print spacing, number of drops and soil layer geotechnical properties and four improvement depth of relative degree as output variables. Input and output data are extracted from the reliable scientific literature. Following development of the fuzzy model, the results of this study has been validated with the results of valid Dynamic Compaction operation in the world. Then as a case study with using the prepared model, Dynamic Compaction Operation in Shahid Rajaee Port in Iran has been analyzed. The results indicate that the effect of tamper weight is greater than the height of tamping and print spacing is in third importance grade. The interaction between tamper weight and dropping height plays the greatest role in the design procedures. Studies show that the optimal tamper radius for most compaction patterns with medium to high applied energies is equal 1.5 to 2 meters, the optimal dropping numbers are equal 25 and optimal print spacing is equal 6 to 7 meters so using this pattern leads to obtain maximum improvement depth.

کلیدواژه‌ها [English]

  • Dynamic Compaction
  • Fuzzy system
  • Relative improvement depth
  • Granular soils
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