تخمین همگرایی تونل‌های دایروی عمیق با استفاده از منحنی تنش- کرنش توده‌سنگ اطراف آن

نوع مقاله : مقاله کامل پژوهشی

نویسندگان

1 دانشکده مهندسی عمران، دانشگاه تبریز

2 دانشکده مهندسی عمران دانشگاه تبریز

چکیده

     این مطالعه در ارتباط با ارائه روش تحلیلی جدیدی است که بر اساس آن، تغییر شکل شعاعی دیواره تونل­های دایره­ای با استفاده از منحنی تنش- کرنش توده­سنگ اطراف تونل تخمین زده می­شود. کرنش دیواره تونل از مجموع بخش "الاستیک" منحنی و بخش "پلاستیک" آن شامل دو قسمت نرم­شوندگی موسوم به قسمت "نرم­شوندگی کرنش اولیه" و قسمت "نرم­شوندگی ثانویه" حاصل می­شود. در این منحنی، شیب قسمت نرم­شوندگی اولیه ضریبی از شیب بخش الاستیک منحنی بوده که این ضریب تابعی از عمق تونل و کیفیت اولیه توده­سنگ است. با این اصول، شیب ناچیز قسمت نرم شوندگی ثانویه نیز با توجه به کیفیت توده­سنگ شکسته شده محاسبه می­شود. زمان انتقال بین این دو قسمت، برحسب تنش و به صورت ضریبی از مقاومت ماندگار توده­سنگ پیشنهاد می­شود. محاسبه این ضریب با نمودارهایی برحسب عمق تونل و خصوصیات مکانیکی توده­سنگ ارائه می­شود که از منطبق کردن نتایج این روش با نتایج روش­های تحلیلی معتبر به دست آمده­اند. مثال­های حل شده و مقایسه نتایج، سادگی و کارایی این روش را برای تخمین اولیه کرنش دیواره تونل نشان می­دهد.
 

کلیدواژه‌ها


عنوان مقاله [English]

Application of the Stress-Strain Curve of Rock Mass to Estimate the Convergence of Deep Circular Tunnels

نویسندگان [English]

  • Masoud Ranjbarnia 1
  • Nima Rahimpour 2
1 Faculty of Civil Engineering, University of Tabriz
2 Faculty of Civil Engineering, University of Tabriz
چکیده [English]

The prediction of tunnel convergence at great depth is the important factor in tunneling design. A large number of analytical solutions have been presented for circular tunnels. However; it is not an easy task to use them in practice due to their either complexity or difficulty of stepwise computations, particularly when the stress-strain behavior of rock mass is the strain softening.
Therefore; in this study, a simple analytical approach is presented to estimate circular tunnel convergence using the stress- strain curve of rock mass located on tunnel wall. This curve is obtained based on values of the principle stresses as well as their variation on tunnel wall due to tunnel face advancement.

کلیدواژه‌ها [English]

  • Analytical approach
  • Circular tunnel
  • Tunnel Convergence
  • Stress-strain curve
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