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
Abbaspour M, Vaghefi M, Ghodsian M, 2009. Investigation of the effect of the T shape spur dike’s submergence ratio on the bed topography in a 90 degree bend. 9th Iranian hydraulic conference, Tarbiat Modarres University, Tehran, Iran. (In Farsi)
Ezzeldin MM, Saafan TA, Rageh OS, Nejm LM, 2007. Local scour around spur dikes. 11th International Water Technology Conference, Sharm El-sheikh, Egypt.
Fang D, Sui J, Thring R. and Zhang H, 2006. Impacts of dimension and slope of submerged spur dikes on local processes- An experimental study. International Journal of Sediment Research 21 (2): 89-100.
Fazli M, Ghodsian M, Salehi Neyshabouri SAA, 2007. Investigation of scour around an impermeable spur dike in bend. 6th Iranian hydraulic conference, Shahrekord University, Iran. (In Farsi)
Fazli M, Ghodsian M, Salehi Neyshabouri SAA, 2008. Bed topography changes in a 90 degree bend in different flow conditions. Modarres Technical and Engineering Journal. 35: 123-142. (In Farsi)
Jamieson EC, Rennie CD and Townsend RD, 2013. 3D Flow and sediment dynamics in a laboratory channel bend with and without stream barbs. Journal of Hydraulic Engineering139: 154-166.
Jasemi Zargani E, Kashefipour SM, 2014. Investigation of Different Modes of Riprap Failure for Submerged Spur Dike Water and Soil Science- University of Tabriz. 24(3): 89-99. (In Farsi)
Kuhnle RA, Alonso CV and Shields FD, 2002. Local scour associated with angled spur dikes. Journal of Hydraulic Engineering. 128 (12):1087-1093.
Masjedi A and Peymani Foroushani E, 2012. Reduction of local scour by shape of single spur dike in river bend. 9th ISE conferrence, Vienna.
Masjedi A, Morattab B and Savari A, 2011. Study of effect angle on scour hole submerged vanes on scour hole at flume bend. World Applied Sciences Journal 13 (9): 2049-2051.
Pirayesh A, 2014. Investigation of the effect of the spur dike angle with the river wall on erosion. Journal of Retrofitting and Rehabilitation Industry 29: 61-66. (In Farsi)
Rahman M, Nakagawa H, Khaleduzzaman A, Ishigaki T and Muto Y, 2004. On the formation of stable river course. Annuals of Disaster Prevention Research Institute, Kyoto University. (47B): 601-616.
Rahman M, Nakagawa H, Ito N, Haque A, Islam T, Rahman MR and Hoque MM, 2006. Prediction of local scour depth around Bandal-like structures. Annual Journal of Hydraulic Engineering JCE(50): 163-168.
Safarzadeh A, Salehi Neyshabouri S A A, 2005. Hydrodynamic Study of Turbulent Flow Pattern in River Bend Using 3D Numerical Model. Journal of Iran-Water Resources Research 1(3): 72-84. (In Farsi)
Shojaeian Z, Kashefipour SM, Mosavi Jahromi SH, Shafaee Bajestan M, 2015. Study on the Longitudinal Velocity Profiles Around Series of Bandal-like Spur Dike. Water and Soil Science- University of Tabriz 25(2): 1-11. (In Farsi)
Shojaeian Z, Kashefipour SM, Mosavi Jahromi SH, 2015. Experimental Study of the Effect of Permeability Percentage of Bandal Like Spur Dike on Maximum Depth of Scour Hole. Water and Soil Science- University of Tabriz. 25(3):105-116. (In Farsi)
Shojaeian Z, Kashefipour SM, Mosavi Jahromi SH, Shafaee Bajestan M, 2014. Experimental Study on The Local Scouring of Series of Bandal-Like spurs in Clear Water Condition. Journal of Irrigation Science and Engineering 38 (2): 21-32. (In Farsi)
Teraguchi H, Nakagawa H, Kawaike K, Baba Y and Zhang H, 2010. Morphological changes induced by river training structures: bandal-like structures and Groins. Annuals of Disaster Prevention Research Institute, Kyoto University. (53B): 505-518.
Teraguchi H, Nakagawa H and Kawaike K, 2011. Effects of hydraulic structures on river morphological processes. International Journal of Sediment Research 26: 283-303.
Uddin MJ, Hossain MM, Ali MS, 2007. Local scour around submerged bell mouth groin for different orientations. Journal of Civil Engineering 39 (1): 1-17.
Yun L, Baomin W and Yongqiang L, 2012. Research on application of removable non-rescue submerged groins in Lower Yellow River Training Works. Procedia Engineering 28: 781 – 785.
Zhang H, Nakagawa H, Baba Y, Kawaike K and Teraguchi H, 2010.Three dimensional flow around bandal- like structures. Annual Journal of Hydraulic Engineering JSCE 54: 175-180.