مطالعة آزمایشگاهی تأثیر سپری‏ های قائم و مایل در کنترل نشت و پدیدة جوشش در پی سازه‏ های آبی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 کارشناس ارشد ژئوتکنیک دانشگاه یاسوج

2 استادیار گروه خاک‌شناسی دانشگاه یاسوج

3 استادیار گروه مهندسی عمران دانشگاه یاسوج

چکیده

در زمینة نشت از پی سازه‏های آبی تا کنون تحقیقات فراوانی، به‌ویژه در قالب مدل‌های عددی، انجام شده است که برای ارزیابی صحت آن‌ها به داده‌های صحرایی و آزمایشگاهی نیاز است. در این تحقیق، برای بررسی اثر عوامل مؤثر بر پدیدة جوشش از پی سازه‏های هیدرولیکی مستقر بر پی‏های آبرفتی، یک مدل آزمایشگاهی به طول 2/2 و ارتفاع 8/0 و عرض 4/0 متر، با استفاده از اسکلت فولادی و جداره‌های پلکسی‏گلاس ساخته و آماده شد. پردة آب‌بند نیز، به منزلة متغیر عمقی، از ورقة‌ پلکسی‌گلاس ساخته شد. در این تحقیق تأثیر موقعیت، عمق دیوارة سپری بر مقدار دبی نشت، و گرادیان خروجی در قالب نمودارهای بی‌بعد آمده است. این تحقیق نشان داد در صورت استفاده از پردة آب‏بند قائم در نسبت عمق پردة آب‏بند ( ) به ضخامت پی ( ) برابر  و پردة آب‏بند مایل در نسبت  با بیشترین نسبت تراز آب بالادست  پدیدة جوشش رخ نمی‏دهد و مقدار دبی نشت و گرادیان هیدرولیکی در محدودة مجاز و مناسبی قرار دارند.



 

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Laboratory Study of Vertical and Inclined Sheet Pile Effects on Seepage Control and Sand Boiling Phenomenon through Alluvial Foundation of Hydraulic Structures

نویسندگان [English]

  • Mehdi Yousefi 1
  • Mohammad Sedghi Asl 2
  • Mansoor Parvizi 3
1 M.A. student in Geotechnics, Yasuj University, Yasuj
2 Assistant Professor of Soil Science, Agricultural College, Yasouj University; Yasouj
3 Assistant Professor of Civil Engineering, Faculty of Engineering, Yasouj University; Yasouj
چکیده [English]

So far, for an analysis of seepage under hydraulic structures much research has been
conducted in the form of numerical models. However, few field and laboratory works
have been performed to study the boiling phenomena for evaluating numerical models.
Throughout the present work, a laboratory model was built to simulate seepage and its
controlling measures under sheet piles. The model consisted of a 2.2 m long, 0.8 m deep
and 0.4 m wide flume, in which vertical sheet piles were provided by Perspex sheets. The
flume was made up of a steel frame, Perspex as well as thick glass sheets. The effect of
position and depth of the sheet pile on the seepage flow, exit gradient and uplift pressure
have been demonstrated in the form of dimensionless curves. The results indicate that the
ratios d/D=0.44 and d/D=0.34 with a maximum upstream water level of h/hm=1.0 form
the best possible depths, for both vertical and inclined sheet piles in the depth of the
foundation sheet pile. In other words, inclined sheet piles are much more effective in
reducing and controlling seepage, uplift pressure and hydraulic gradient than the vertical
ones.

کلیدواژه‌ها [English]

  • alluvial foundation
  • Boiling
  • Hydraulic Structures
  • Sheet pile
  • Seepage
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