ارزیابی ریسک ایمنی سدها (مطالعه موردی: ریسک سیلاب در سد گلستان)

نوع مقاله : مقاله پژوهشی

نویسندگان

1 کارشناس ارشد، دانشکده محیط زیست، دانشگاه تهران

2 دانشیار، دانشکده محیط زیست، دانشگاه تهران

3 دانشیار، دانشکده مهندسی عمران، دانشگاه تهران

چکیده

ایمنی سد در صنعت سدسازی از مهم ترین مسائل در هنگام طراحی، ساخت و بهره برداری به شمار می رود. امروزه استفاده از فنون ارزیابی کمی ریسک در مدیریت ایمنی سدها (به ویژه در کشورهای توسعه یافته)، به سرعت در حال گسترش است. اما این رویکرد جدید به مهندسی سد و ایمنی در ایران همچنان ناشناخته بوده و تحقیقات محدودی در این زمینه انجام شده است. در این مقاله، در ابتدا روش های ارزیابی ریسک در ایمنی سدها مورد بررسی قرار گرفته و روش ارزیابی بر اساس دستورالعمل کمیته ملی سدهای بزرگ استرالیا (ANCOLD ) تشریح شده است. در ادامه، ایمنی سد گلستان به عنوان مطالعه موردی بررسی شده و با توجه به روش پیشنهادی، ارزیابی ریسک شکست این سد تحت خطر وقوع سیل در بالادست آن انجام گرفته است. احتمال شکست سد گلستان با استفاده از روش ارزیابی درخت رویداد(ETA)محاسبه شده و تعداد تلفات جانی به علت سیل ناشی از شکست سد نیز از طریق روش رایج در اداره اصلاح اراضی آمریکا(USBR)موسوم به 06 - DSO-99 تخمین زده شده است. در آخر از طریق مقدار ریسک بدست آمده و مقایسه آن با معیارهای مختلف برای سطح ریسک قابل قبول، این نتیجه گیری حاصل شد که مقدار ریسک شکست سد گلستان بر اثر وقوع سیل در بالادست آن، غیرقابل قبول بوده و اقدامها برای کاهش ریسک فوری ضروری است.

کلیدواژه‌ها


عنوان مقاله [English]

Dam Safety Risk Assessment (Case Study: Flood Risk for Golestan Dam)

نویسندگان [English]

  • M. Mahmoudian-Shoushtari 1
  • B. Malekmohammadi 2
  • M. A. Banihashemi 3
1 M.Sc., Faculty of Environment, University of Tehran
2 Associate Professor, Faculty of Environment, University of Tehran
3 Associate Professor, Faculty of Civil Engineering, University of Tehran
چکیده [English]

In dam construction industry, the safety of dam is one of the most important challenges that should be
considered in design, construction and operation phase. Recently, use of quantitative risk analysis, as
a useful tool in dam safety risk management, is rapidly increasing. In this paper, first, risk assessment
methods in dam safety are investigated and australian national committee on large dams (ANCOLD)
guideline for dam safety risk assessment is detailed. Then, as a case study, safety of Goleastan dam,
in northeast of Iran, is assessed considering risk analysis approach for upstream flood hazard. For
calculating the probability of failure of dam, the various methods were assessed and finally event tree
analysis (ETA), as most commonly method in dam safety risk analysis was used. The number of life
losses due to flooding of Golestan dam break is estimated based on united states bureau of reclamation
(USBR) methodology, known as DSO-99-06. Finally, according to calculated risk and comparing with
different criteria for acceptable risk, it is obvious that the risk of Golestan dam break due to upstream
flood is unacceptable and immediate risk reduction measures are necessary.

کلیدواژه‌ها [English]

  • Safety Risk Assessment
  • Golestan Dam
  • Evant Tree Analysis
  • Flood Hazard
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