بررسی آزمایشگاهی کنترل فرسایش در پایین‌دست سرریزهای پلکانی با استفاده از ساختار میکروسیلیس و نانو مواد

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه عمران، دانشکده فنی و مهندسی، دانشگاه زنجان، ایران

2 دانشیار گروه مهندسی عمران، دانشکده فنی و مهندسی، دانشگاه مراغه ، ایران

3 گروه عمران، دانشکده فنی و مهندسی، دانشگاه صنعتی سهند، ایران

4 مربی گروه عمران دانشگاه مراغه، مراغه، ایران

چکیده

مواد نانو ساختار به دلیل دارا بودن خاصیت ضد آب، می‌توانند برای کاهش آبشستگی بستر رسوبی کاربرد داشته باشند. در این پژوهش تاثیر افزودن رس و نانومواد و میکروسیلیس به مصالح بستر رسوبی پایین‌دست سرریز پلکانی در کنترل فرسایش و آبشستگی آن به‌عنوان یک راه‌حل غیرسازهای بررسی شده است. در گام نخست به ارزیابی تاثیر تعداد پله‌ها و رژیم جریان ایجادشده بر روی پله‌ها در میزان آبشستگی پایین‌دست پرداخته شد. نتایج نشان داد که با افزایش تعداد پله در شیب شوت یکسان و در رژیم جریان غیرریزشی ایجادشده بر روی پله‌ها مقدار عمق و طول آبشستگی در پایین‌دست سرریز پلکانی افزایش می‌یابد. در گام بعدی تاثیر افزودنی‌های تزریقشده به بستر رسوبی پایین‌دست سرریز در این تعداد پله از سرریز پلکانی و رژیم جریان غیر ریزشی برررسی گردید. نتایج آزمایش‌ها از تاثیر مثبت رس و ترکیب آن با نانورس و میکروسیلیس در بهبود و کاهش پروفیل آبشستگی در پایین‌دست سرریز پلکانی حکایت دارد. بهترین عملکرد از بین 3 نوع ترکیب مختلف مربوط به ترکیب رس به همراه نانورس و میکروسیلیس بوده که نسبت به مدل شاهد در کاهش عمق و طول آبشستگی به‌ترتیب 48/74 و 46/38 درصد سهم داشتند. در تزریق رس به بستر رسوبی، عمق و طول آبشستگی به‌ترتیب 35/63 و 20/88 درصد و برای ترکیب رس به همراه نانورس بهترتیب 41/41 و37/75 درصد کاهش داشتند. این نتایج می‌تواند بیانگر تاثیر مثبت و قابل ملاحظه رس و نانورس و میکروسیلیس در کنترل مکانیسم آبشستگی بستر پایین‌دست سازه‌های هیدرولیکی به ویژه در دبی‌های سیلابی باشد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental Investigation of Downstream Erosion Control of Stepped Spillways using Microsilica - Structured and Nano Materials

نویسندگان [English]

  • Amir Ghaderi 1
  • Rasoul Daneshfaraz 2
  • Reza Zaerkabehc 3
  • Forough Ashkan 4
1 Department of Civil Engneering, Faculty of Engneering, University of Zanjan, Iran
2 Dept. of Civil Engineering, University of Maragheh, Iran
3 Department of Civil Engneering, Faculty of Engneering, Sahand University Of Technology, Iran
4 A Faculty Member, Maragheh University, Maragheh, Iran
چکیده [English]

Nano-structured materials are waterproof, and they can be used for the reduction of scouring in alluvial beds. In this research, the impact of clay additive and Nanomaterials and Silicafume to sedimentary bed materials of stepped spillway on controlling erosion and scouring are investigated as a Nonstructural solution. Firstly, the effect of the number of steps and flow regime on downstream scouring were studied. The results show that by increasing the number of steps on the same slop of chute and in a skimming flow regime on the steps, the depth and length of the scouring on the downstream of the stepped spillway increases. Then the impact of some injected additives to the sedimentary bed with the same number of steps and skimming flow regime was investigated. The results prove the positive effect of clay and its mixture with Nano-clay and Silicafume on the reduction of scouring length and depth reduction on the weir downstream. The best performance between three different compositions is related to the mixture of clay with Nano-clay and Silicafume in which they contributed in reduction profile of scoring by 48.74% and 46.38% respectively compared with the reference model. At the same time injection of clay to the sedimentary bed reduced the depth and length of scouring by 35.63% and 20.88% and injection of clay with Nanoclay reduced the depth and length of scouring by 41.41% and 37.75% respectively. These results can state the success of clay, Nano-clay, and Silicafume on the scouring control mechanism at downstream of hydraulic structures, especially in flood discharges.

کلیدواژه‌ها [English]

  • Bed stabilization
  • Number of steps
  • Scouring in downstream of a stepped
  • spillway
  • Silicafume
  • Nanoclay
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