شبیه‌سازی عددی تاثیر لوله‌های‌ زهکش بر نیروی بالابرنده، گرادیان هیدرولیکی خروجی و نشت در سد‌های وزنی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 Tabriz University, Agricultural faculty, Irrigation department

2 گروه مهندسی آب دانشگاه تبریز

3 مهندسی آب، کشاورزی،تبریز،تبریز،ایران

چکیده

در این تحقیق تاثیر قطر و موقعیت لوله­های زهکش در پی سد­های­ وزنی بر روی نیروی بالابرنده ،گرادیان هیدرولیکی خروجی و نشت مورد بررسی قرار گرفت. برای نیل به این هدف از نرم افزار Seep/w که متعلق به بسته نرم افزاری Geo-Studio می­باشد استفاده و پی یک سد وزنی شبیه­سازی گردید. نتایج نشان داد که وجود لوله­های­ زهکش در زیر سد وزنی، باعث کاهش 4، 6 و 9 برابری به ترتیب برای نیرو­ی بالابرنده، گرادیان هیدرولیکی خروجی و نشت می­گردد. تعبیه همزمان دو لوله زهکش که یک چهارم عرض کف سد وزنی (0/25L) از هم فاصله دارند، در پاشنه  سد وزنی و در عمق0/26D کمترین نیروی بالابرنده را نتیجه داد (D عمق نفوذپذیر پی سد است). همچنین با مشخص شدن بهترین موقعیت برای تعبیه لوله­های زهکش مشاهده گردید که کارگذاری لوله­های زهکش در این موقعیت­ها باعث کاهش 41 تا 67 درصدی در حجم سد وزنی مورد مطالعه و افزایش 2 تا 3 برابری ضریب اطمینان در مقابل واژگونی سازه مورد نظر می­گردد.همچنین مشخص گردید که انتخاب قطر لوله زهکش تخلیه تاثیر کمتری بر نیروی بالابرنده، گرادیان هیدرولیکی خروجی و نشت دارد و تابع ملاحظات اجرایی می­باشد. برای اعتبار سنجی، روش عددی به­کار رفته در این پژوهش با روش آزمایشگاهی دیگران نیز مقایسه گردید و تطابق مناسبی مشاهده شد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical Simulation of Effect of Drain Pipe in Uplift Force, Exit Hydraulic Gradient and Seepage in Gravity Dams

نویسندگان [English]

  • Farzin Salmasi 1
  • Hadi Arvanaghi 2
  • Ali Taheri aghdam 3
2 Water Engineering Department, Faculty of Agriculture, University of Tabriz, Tabriz, Iran
3 Water and Science Enginreering, tabriz,tabriz,iran
چکیده [English]

In this study, the effects of diameter and location of drain pipes in uplift force, exit hydraulic gradient and seepage in the foundation of gravity dams are investigated. For this purpose, the SEEP/W software as a subgroup of Geo-Studio software is implemented and the foundation of a gravity dam is simulated. The results showed that the existence of drain pipes under the gravity dam reduce 4, 6, and 9 times of uplift force, exit hydraulic gradient and seepage, respectively. Installation of two drain pipes with 0.25L distance from each other and in the depth of 0.26D near the dam heel presents a more suitable position with respect to uplift force reduction (D is the pervious foundation depth). Also, by defining the best position for the location of drain pipes, it was observed that drainage pipes in these situations reduce 41-67% in the volume of the studied dam and increase the safety factor up to 2 to 3 times against the dam overturning. It is also found that the drainage pipe diameter has less effect on the uplift force, exit hydraulic gradient and seepage and is controlled by the rules of the executive. For validation, the numerical method used in this study was compared with the laboratory method by others and a suitable match was observed.

کلیدواژه‌ها [English]

  • Drain pipe
  • Exit Hydraulic Gradient
  • Finite elements method
  • gravity dam
  • Seepage
  • Uplift force
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