بررسی تاثیر خصوصیات درزه‌ها بر روی جریان پایدار آب ورودی به تونل- مطالعه‌ی موردی: تونل سوم کوهرنگ

نوع مقاله: یادداشت فنی

نویسندگان

1 دانشجوی دکترای تخصصی مهندسی معدن؛ گرایش استخراج؛ دانشکده‌ی مهندسی معدن، نفت و ژئوفیزیک؛ دانشگاه شاهرود

2 استادیار؛ دانشکده‌ی مهندسی معدن، نفت و ژئوفیزیک؛ دانشگاه شاهرود

3 دانشیار؛ دانشکده‌ی مهندسی معدن، نفت و ژئوفیزیک؛ دانشگاه شاهرود

4 کارشناس ارشد مکانیک سنگ؛ مهندسین مشاور‌ زایندآب

چکیده

بدون تردید جریان آب در پروژه‌های تونلسازی یکی از مسائلی است که می‌تواند آثار مخرب فراوانی بر طرح داشته و فعالیت تونلسازی را کاملا تحت تاثیر قرار دهد. بنابراین لازم است محل و مقدار جریان آب به درون تونل تا حد امکان پیش‌بینی و در ملاحظات تونلسازی در نظر گرفته شود. از سوی دیگر تجربیات گذشته نشان داده است پیش‌بینی دقیق مقدار نفوذ آب در تونل‌های حفر شده در سنگ به دلیل عدم در نظر گرفتن تمامی عوامل تاثیرگذار بر جریان آب به خصوص شرایط و خصوصیات ناپیوستگی‌ها امکان‌پذیر نیست. در این مقاله برای مدلسازی تاثیر خصوصیات ناپیوستگی‌ها بر روی نرخ جریان آب ورودی به تونل در مقطع کیلومتراژ 897+1 تا 950+1 تونل کوهرنگ 3، از نرم‌افزار اجزای گسسته‌ی UDEC استفاده و با تغییر خصوصیات ناپیوستگی‌های منطقه، نرخ جریان ورودی به تونل بررسی شده است. نتایج حاصل از این پژوهش نشان داده است تغییر خصوصیات ناپیوستگی‌ها در نرخ جریان پایدار آب در تونل دارای تاثیر بسزایی است و از میان این خصوصیات، میزان بازشدگی درزه، بیش‌ترین تاثیر را بر نرخ جریان آب ورودی به تونل دارد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of the Influence of Joints Properties on the Steady State Water Flow into the Tunnel - A Case Study: Koohrang 3 Tunnel

نویسندگان [English]

  • Ramin Rafiee 1
  • Ahmad Ramezanzadeh 2
  • Farhang Sereshki 3
  • Esmaeil Movahedinejad 4
1 Ph.D. Candidate in Mining Eng.; Faculty of Mining Eng., Petroleum, and Geophysics; University of Shahrood
2 Assistant Professor; Faculty of Mining Eng., Petroleum, and Geophysics; University of Shahrood
3 Associate Professor; Faculty of Mining Eng., Petroleum, and Geophysics; University of Shahrood
4 M.Sc. in Rock Mechanics; Supervisor of Zayand-Ab Consulting Engineering Company
چکیده [English]

Water flow in tunneling projects is one of the main issues that can affect the plan and activity of the tunneling. Therefore, it is necessary to predict the location and the amount of water flow into the tunnel. Past experience have shown that the accurate prediction of water flow in the excavated tunnels is not possible due to the lack of consideration all influencing factors, especially the properties and condition of joints. In this paper, in order to investigate the effect of joints properties on the water flow rate, the cross sections of Koohrang 3 from 1+897 to 1+950 km have been modeled using UDEC software. By changing the properties of joints, the flow water rate into the tunnel has been assessed. The results of this study have shown that changing the properties of joints has significant influence on the steady state water flow. Among these properties, the aperture of joint has the most significant effect on water flow rate in the tunnel.
 
Introduction
Analysis of water flow is necessary for construction of underground structures. In this analysis, the possibility of any kind of change in the ground water behavior and flow rate should be considered. In this paper, the effect of joints properties on the water flow rate using numerical modeling has been studied.
 
Methodology and Approaches
Joints properties have great influence on the water flow rate into tunnels. In order to investigate the effect of joints characteristics on the water flow rate, the cross sections of Koohrang 3 tunnel have been modeled using UDEC software. By changing the joints properties in the tunnel, the water flow rate into the tunnel has been assessed. Finally, The water flow rates obtained from the numerical modeling results has been compared with the values obtained from the analytical methods.
 
Results and Conclusions
The results of this study have shown that the increase of the joint spacing reduce the water flow rate into the tunnel due to the increase of size of formed blocks. In addition, increase of the joint aperture substantially increases the amount of water flow into the tunnel. Moreover, by increasing the joint orientation from 30 to 120 degrees, the maximum water flow occurs at the angle between 50 and 70 degrees. According to the results of this investigation on the joints properties, the joint aperture has the greatest effect on the water flow rate into the tunnel.

کلیدواژه‌ها [English]

  • Koohrang 3 tunnel
  • Discrete Element Method
  • Water flow rate
  • Joint properties
  • joint aperture
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