ارزیابی ریسک روگذری سدهای خاکی با مدل پویایی سیستم‌ها تحت شبیه‌سازی مونت کارلو و روش اَبَرمکعب لاتین، مطالعه موردی: سد حاجیلر‌چای

نوع مقاله: مقاله پژوهشی

نویسندگان

1 گروه مهندسی آب، دانشکده مهندسی عمران، دانشگاه تبریز، تبریز،ایران

2 استاد، دانشکده مهندسی عمران، دانشگاه تبریز، تبریز، ایران

چکیده

ارزیابی ریسک سازه‌ها مخصوصاً سدها، از موضوعاتی‌ است که اخیراً مورد توجه محققین می‌باشد. به کمک نظریه قابلیت اطمینان و ریسک می‌توان عدم قطعیت پارامترهای تصادفی را به صورت روابط ریاضی در روند طراحی استفاده نمود. در این مقاله عدم قطعیت های مختلف به همراه سیلاب و باد با دوره های بازگشت مختلف به طور مجزا و همزمان در مدل پویایی سیستم‌ها برای ارزیابی ریسک روگذری سد خاکی جاجیلرچای مورد استفاده قرار گرفته است تا بتوان تمهیدات لازم را برای کاهش ریسک روگذری سد مذکور اتخاذ نمود. به منظور برآورد ریسک در مدل مدنظر از روش‌های شبیه‌سازی مونت‌کارلو و نمونه‌گیری ابر‌مکعب لاتین با تعداد تکرار مختلف استفاده شده است. نتایج ضمن نشان دادن توانایی پویایی سیستم ها در محاسبه ریسک روگذری و افزایش آن در شرایط توام سیلاب و باد، نشان می‌دهد که باز بودن دریچه تخلیه‌کننده تحتانی سد حاجیلر‌چای به طور متوسط باعث کاهش ۹/۲۰ درصد ریسک روگذری در اثر سیلاب و ۴/۱۰ درصد در اثر سیلاب و باد می‌گردد. همچنین میانگین ریسک روگذری محاسبه شده به روش مونت‌کارلو در اثر سیلاب حدوداً ۴/۳۰ درصد و در اثر توأم سیلاب و باد حدوداً ۳/۵۰ درصد از میانگین مقادیر روش ابر‌مکعب لاتین بیشتر می‌باشد. در شرایط مشابه، شاخص اعتماد‌پذیری نتایج روش مونت‌کارلو از روش ابر‌مکعب لاتین بیشتر بوده و زمان لازم برای شبیه‌سازی آن کمتر می‌باشد. بر پایه این نتایج، روش پویایی سیستم‌ها با مونت کارلو ابزار کارآمدی در محاسبه ریسک روگذری سدهای خاکی می‌باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation of earth dam overtopping risk by system dynamics, Monte-Carlo simulation and Latin Hypercube Sampling methods (case study: Hajilarchay Dam, Iran)

نویسندگان [English]

  • Ali Ebrahimzadeh 1
  • Mahdi Zarghami 2
  • Vahid Nourani 2
1 Department of Water Engineering, Faculty of Civil Engineering, University of Tabriz, Tabriz, Iran
2 Professor, Faculty of Civil Engineering, University of Tabriz, Tabriz, Iran
چکیده [English]

Risk assessment of structures, especially dams, has recently been one of the main topics that are considered by researchers. Risk analysis make possible to estimate uncertainties coming up from randomness of parameters in the models which are applicable in designing process. In this paper, different uncertainties along with flood and wind with various return periods segregated and simultaneously were exploited to mitigate the overtopping risk of Hajilarchay earth dam. To assess the risk in the proposed model, we used Monte-Carlo simulation (MCS) and Latin hypercube sampling (LHS) method with different iterations through system dynamics approach. The results proved the effectiveness of system dynamics approach on overtopping risk assessment for earth dams which showed the influences of different parameters on overtopping risk besides flood and wind. Furthermore, the results showed that opening the bottom outlet of Hajilarchay Dam may reduce the average overtopping risk as much as 9.20 and 4.10 percent due to just flood and due to flood and wind, respectively. In addition results showed that the average overtopping risk estimated from MCS method due to just flood and due to flood and wind were about 4.30 and 3.50 percent, respectively, more than that the results obtained by the LHS method. Also the reliability index obtained by the MCS method was higher than LHS method and MCS method has faster calculation in compare to the LHS. Finally, we can conclude that system dynamics approach along with MCS is a very effective tool to estimate the overtopping risk of earth dams.

کلیدواژه‌ها [English]

  • Overtopping Risk
  • system dynamics
  • Uncertainty
  • Monte-Carlo simulation
  • Latin Hypercube Sampling
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