بررسی اثر استغراق و زاویه آبشکن باندال‌لایک نسبت به ساحل بر بیشینه عمق آبشستگی اطراف آن در قوس ملایم 90 درجه

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری سازه‌های آبی، دانشکده مهندسی علوم آب، دانشگاه شهید چمران اهواز

2 استاد سازه‌های آبی، دانشکده مهندسی علوم آب، دانشگاه شهید چمران اهواز

3 استادیار سازه‌های آبی، دانشکده مهندسی علوم آب، دانشگاه شهید چمران اهواز

چکیده

سازه باندال­لایک نوعی آبشکن است که به­صورت ترکیبی از آبشکن نفوذپذیر و نفوذناپذیر ساخته می­شود. این سازه معمولا در شبه قاره هند به منظور کنترل فرسایش و بهبود عمق جریان برای کشتی­رانی در رودخانه­های آبرفتی احداث می­گردد. این آبشکن می­تواند جایگزین مناسبی برای آبشکن­های معمول محسوب شود. در این مطالعه اثر استغراق و زاویه قرارگیری آبشکن باندال­لایک نسبت به ساحل بر بیشینه عمق آبشستگی اطراف آبشکن در فلومی با قوس ملایم 90 درجه بررسی شده است. بدین منظور سری باندال­لایک­ها با سه زاویه 60، 90 و 120 درجه درون فلوم جایگذاری شده و با سه نسبت استغراق متفاوت (16/1، 65/1، 15/2) و تحت شرایط هیدرولیکی متفاوت (اعداد فرود 21/0، 23/0، 26/0، 29/0) مورد آزمایش قرار گرفته­اند. نتایج نشان داد که آبشکن­های با زاویه 90 درجه (قائم) دارای بیشترین و آبشکن­های با زاویه 60 درجه (جاذب) دارای کمترین میزان آبشستگی می­باشند. هم­چنین با افزایش استغراق سازه­ها بیشینه عمق آبشستگی در اطراف آن­ها نیز افزایش می­یابد.

کلیدواژه‌ها


عنوان مقاله [English]

Investigating Effect of Submergence and Angle of Bandal-Like Structure on the Maximum Scour Depth in a Mild 90-Degree Bend

نویسندگان [English]

  • P Koochak 1
  • SM Kashefipour 2
  • M Ghomeshi 2
  • A Fathi 3
1 Ph. D. Student, Faculty of Water Science Engineering, Shahid Chamran University, Ahvaz, Iran
2 Prof. of Hydraulic Structure, Faculty of Water Science Engin., Shahid Chamran Univ., Ahvaz, Iran
3 Assist. Prof. of Hydraulic Structure Engin., Faculty of Water Science Engin., Shahid Chamran Univ., Ahvaz, Iran
چکیده [English]

Bandal-like structure is a kind of a spur dike which is a combination of a permeable and an impermeable spur dikes that are usually used in Indian Sub-Continents for riverbank protection and improvement of navigation conditions in alluvial rivers. It is considered as a suitable alternative for these spur dikes. In this research effect of the submergence and angle of the bandal-like structure on the maximum scour depth in a 90 degrees’ mild bend flume was investigated. Therefore, a series of bandal-like structures were placed in the flume with three different angles (60, 90, 120) and three different submergence ratios (1.16, 1.65, 2.15) and were examined under four different Froude numbers (0.21, 0.23, 0.26, 0.29). The results showed that the maximum and minimum scour depths belonged to the bandal-like structures with 90 and 60 degrees angles respectively. Also by increase of the submergence ratio the maximum scour depth was increased.

کلیدواژه‌ها [English]

  • Bandal-like structure
  • Maximum scour depth
  • Submergence ratio
  • Spur dike angle
  • 90-Degree bend
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