تحلیل احتمالاتی پایداری یک سد با استفاده از روش شبیه‌سازی مونت کارلو مبتنی بر روش‌ تعادل حدی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی علوم زمین دانشگاه صنعتی اراک

2 دانشکده مهندسی علوم زمین، دانشگاه صنعتی اراک

چکیده

بررسی پایداری شیروانی‌ها یا شیب‌های خاکی از نظر داشتن پتانسیل ایجاد زمین لغزش‌های عظیم و تخریب مسیرها و سازه‌های مهم، از حساس‌ترین و مهم‌ترین مسائل ژئوتکنیک می‌باشند. تعیین ضریب اطمینان این شیروانی‌ها در پی تحلیل پایداری آن‌‌ها، با وجود تغییرپذیری بسیار پارامترهای خاک، در بسیاری از موارد وجود دارد. در این صورت به منظور پوشش دادن اثر عدم قطعیت‌های موجود ناچار به اعمال یک ضریب اطمینان نسبتاْ بزرگ شده که هزینه‌های زیادی را به دنبال خواهد داشت. در ارزیابی‌‌های احتمالاتی بویژه ارزیابی قابلیت اعتماد، تلاش می‌شود تا با بکارگیری دامنه‌ای از مقادیر ممکن برای متغیرها، دامنه تغییرات تابع هدف تعیین شود و احتمال شکست به جای ضریب اطمینان محاسبه شود. هدف از نگارش این مقاله ارائه یک روش جهت تحلیل احتمالاتی پایداری یک سد خاکی است. در این مقاله با استفاده از ترکیب روش شبیه‌سازی مونت‌کارلو به عنوان یک الگوریتم محاسباتی در نرم افزار Slide و روابط روش بیشاپ (یکی از روش‌های تعادل حدی)، پایداری شیب یک سد خاکی (بعنوان مطالعه موردی) مورد بررسی قرار گرفت. نتایج مدلسازی نشان داد که احتمال شکست سد خاکی در بحرانی‌ترین سطح لغزش با ضریب اطمینان ۳۳۶/۲ معادل صفر برآورد می‌شود. همچنین نتایج تحلیل حساسیتی که بر اساس ارزیابی‌های احتمالاتی انجام شد نشان می‌دهد که متغیر زاویه اصطکاک داخلی مؤثرترین متغیر در تخمین احتمال شکست است. بررسی سد موردنظر در تحقیقات دیگر نشان می‌دهد، ارزیابی این سد در تحقیق حاضر از دقت خوبی برخوردار است. درحالی که استفاده از نرم‌افزار Slide ارزیابی‌ها را آسان‌تر کرده و به آن سرعت بخشیده است.

کلیدواژه‌ها


عنوان مقاله [English]

Probabilistic analysis of the stability of a dam using the Monte Carlo simulation method based on the limit equilibrium method

نویسندگان [English]

  • Hadi Fattahi 1
  • Fateme Jiryaee 2
1 Faculty of Earth Sciences Engineering, Arak University of Technology, Arak, Iran.
2 Faculty of Earth Sciences Engineering, Arak University of Technology, Arak, Iran.
چکیده [English]

Probabilistic slope stability analysis provides a tool for considering uncertainty of the soil parameters in design. In this paper, using Slide software, the Monte Carlo simulation is used as an analytical method to develop probabilistic models of slope stability based on equilibrium methods. The limit equilibrium methods are the most popular approaches in slope stability analysis. These methods are well known to be a statically indeterminate problem, and assumptions on the inter-slice shear forces are required to render the problem statically determinate. In modeling using this methodology, the selected stochastic parameters are internal friction angle, cohesion and unit weight of soil, which are modeled using a truncated normal probability density function (pdf). In this research, the abilities offered using models were presented by using field data obtained from Cannon dam in Iran. The results obtained show that the hybrid Monte Carlo simulation and equilibrium methods can be used successfully for slopes stability assessment.

کلیدواژه‌ها [English]

  • Probabilistic analysis
  • Monte Carlo simulation
  • Slide software
  • limit equilibrium methods
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