تاثیر استفاده همزمان از المان شش پایه و سنگچین جهت کنترل آبشستگی و بررسی اقتصادی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری - ساز های هیدرولیکی -گروه عمران - دانشگاه سیستان و بلوچستان - زاهدان

2 دانشگاه سیستان و بلوچستان

3 استاد گروه آب دانشگاه شهید چمران اهواز

4 استاد گروه مهندسی عمران و محیط زیست، دانشگاه West Indies

چکیده

کنترل آبشستگی پایین دست سرریزهای پرش اسکی یکی از مهمترین مسایلی است که مهندسین هیدرولیک با آن روبرو هستند. در این تحقیق با هدف بررسی کارائی مصالح جدید برای کنترل آبشستگی پایین دست سرریز پرش اسکی، به کمک مطالعات آزمایشگاهی به بررسی کاهش حجم گودال آبشستگی در حضور توام المان شش پایه‌ی بتنی با نام تجاری A-Jack به همراه سنگچین در پایین دست سرریز پرش اسکی در شرایط مختلف هیدرولیکی جریان پرداخته شد. آزمایش‌های انجام شده شامل یک اندازه المان بتنی و دو سایز سنگچین با پنج دبی و سه عمق پایاب متفاوت بوده که در نتیجه با توجه به تغییر عمق پایاب، سرریز در سه وضعیت آزاد، نیمه مستغرق و مستغرق قرار گرفت. نتایج حاکی از آن است که با افزایش عمق پایاب میزان آبشستگی دچار کاهش قابل ملاحظه‌ای شده و با حضور همزمان المان بتنی و سنگ چین میزان حداکثر حجم آبشستگی در بین شرایط مختلف هیدرولیکی تا 100 درصد نسبت به آزمایش‌های شاهد کاهش یافت. همچنین مقایسه اقتصادی بین استفاده از هر یک از دو سازه پوششی سنگ چین و المان شش پایه بتنی در مساحت 100 متر مربعی انجام گرفت. نتایج حاکی از برابری نسبی هزینه دو نوع پوشش دارد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of Concurrent Use of the Six-Legged Element and Rip-Rap for Scour Control with Economic Considerations

نویسندگان [English]

  • Mohammad Rashki Ghaleh Nou 1
  • Mehdi Azhdary Moghaddam 2
  • Mahmood Shafai Bajestan 3
  • Hazi Mohammad Azamathulla 4
1 Ph.D Student- Hydraulic structures- Dep. of Civil Engineering- University of Sistan and Balouchestan- Zahedan
2 University of Sistan and Baluchestan
3 Prof. Faculty of Water Science Engineering, Shahid Chamran University of Ahvaz
4 Professor of Civil & Environmental Engineering, The University of the West Indies, St. Augustine Campus, Trinidad
چکیده [English]

The scour control downstream of the ski-jump spillways is one of the most important issues encountered by hydraulic engineers. In this paper, an experimental investigation was performed to evaluate the reduction in the maximum volume of the scour hole due to the concurrent use of the six-legged concrete elements (A-Jacks) and rip-rap materials in different hydraulic conditions. These elements were placed in the downstream of the ski-jump spillway. The experiments included a single size of concrete element and two sizes of rip-rap with five flow discharges and three tail-water depths. The change in tail-water depth resulted in the spillway having free, semi-submerged and submerged conditions. The results were showed that as scour depth increased, the scouring rate is significantly reduced. By simultaneous usage of concrete elements and rip-rap materials, the maximum scour volume decreased up to 100% in different hydraulic conditions as compared to the control tests. In addition, the results showed that the use of a rip-rap layer is about 80% cheaper than the coating with six-legged elements, which this difference is reduced by increasing the thickness of rip-rap layer.

کلیدواژه‌ها [English]

  • Economic comparison
  • Scouring
  • Six-Legged Elements
  • Ski-Jump Spillway
  • Rip-Rap Layer
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