بررسی تأثیر تابع هدایت هیدرولیکی در تحلیل نشت غیر محصور (مطالعه موردی سد خاکی حسنلو)

نوع مقاله: مقاله پژوهشی

نویسندگان

استادیار گروه مهندسی آب، دانشکده کشاورزی، دانشگاه ارومیه، ارومیه، ایران

چکیده

در این تحقیق اهمیت به­کارگیری توابع نفوذپذیری در تحلیل نشت دائم و غیر دائم (انتقالی) غیر محصور در محیط­های همگن و غیر همگن بررسی شد. برای این منظور حالات مختلف جریان در محیط­های همگن و غیر همگن با لحاظ خصوصیات هیدرولیکی مصالح مستخرج از بانک اطلاعاتی خاک­های غیر اشباع (UNSODA) و به کمک یک مدل کامپیوتری مبتنی بر روش اجزای محدود مطالعه شد. برای اعتبار­سنجی نتایج این تحلیل، از داده‌های ابزار دقیق ثبت شده­ی سد حسنلو طی دوره یکساله استفاده گردید. نتایج بررسی­ها نشان داد که در محیط غیر همگن و سدهای ناحیه­بندی شده، خصوصیات هیدرولیکی مصالح پایین دست نسبت به مصالح بالادست بر موقعیت سطح نشت مؤثرتر است. هم­چنین طبق یافته‌های تحقیق، موقعیت سطح نشت در شرایط به­کارگیری هدایت هیدرولیکی ثابت نسبت به هدایت هیدرولیکی متغیر در شرایط بالا آمدن سطح آب در مخزن رشد آهسته­تری داشته و در عین حال در شرایط پایین افتادن سطح آب در مخزن، سرعت زهکشی مصالح بیش­تر می­باشد. مقایسه داده­های واقعی ثبت شده با نتایج مدل نشان می‌دهد که جهت حصول نتایج واقع بینانه لازم است خصوصیات هیدرولیکی مصالح به­صورت تابع هدایت هیدرولیکی تعریف گردد یا اینکه حداقل برای مصالح پایین دست این شرایط رعایت شود.  

کلیدواژه‌ها


عنوان مقاله [English]

Investigation on the Effects of Hydraulic Conductivity Function in Unconfined Seepage Analysis (Case study: Hassanlu Earth Dam)

نویسندگان [English]

  • Hojat Ahmadi
  • Vahid Rezaverdinejad
Assistant Professor, Department of Water Engineering , Faculty of Agriculture, Urmia University., Urmia., Iran
چکیده [English]

In this research the emphasis of the application of hydraulic conductivity function in seepage analysis through in homogenous and nonhomogeneous medium was investigated. For this aim, different forms of flow in mentioned mediums were analyzed via a finite element numeric model based on hydraulic properties were selected from unsaturated soils database (UNSODA). In order to validate the results annual recorded data in Hassanlu earth dam was used.  The results showed, in nonhomogeneous medium as well as zoned earth dams, the role of downstream material is more significant. Furthermore, the phreatic line in the state of employing constant conductivity in instead in conductivity function rises rapidly in the conditions of rising water lever at the boundaries while in drawdown it drain faster. Comparison between filed data and model results also showed to get realistic results employing of hydraulic conductivity in the form function is essential at least for downstream materials.
 

کلیدواژه‌ها [English]

  • Hydraulic Conductivity Function
  • Material
  • Earth Dam
  • Seepage
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