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vaghefi, Mohammad, moghanloo, Mohammad, Dehghan, Danesh, keshavarz, Arsalan. (1396). Experimental Study of the Effect of Base-level fall at the Beginning of the Bend on Reduction of Scour around a Rectangular Bridge Pier Located in the 180 Degree Sharp Bend. سامانه نشریات, 3(2), 32-46. doi: 10.22055/jhs.2018.24900.1065
Mohammad vaghefi; Mohammad moghanloo; Danesh Dehghan; Arsalan keshavarz. "Experimental Study of the Effect of Base-level fall at the Beginning of the Bend on Reduction of Scour around a Rectangular Bridge Pier Located in the 180 Degree Sharp Bend". سامانه نشریات, 3, 2, 1396, 32-46. doi: 10.22055/jhs.2018.24900.1065
vaghefi, Mohammad, moghanloo, Mohammad, Dehghan, Danesh, keshavarz, Arsalan. (1396). 'Experimental Study of the Effect of Base-level fall at the Beginning of the Bend on Reduction of Scour around a Rectangular Bridge Pier Located in the 180 Degree Sharp Bend', سامانه نشریات, 3(2), pp. 32-46. doi: 10.22055/jhs.2018.24900.1065
vaghefi, Mohammad, moghanloo, Mohammad, Dehghan, Danesh, keshavarz, Arsalan. Experimental Study of the Effect of Base-level fall at the Beginning of the Bend on Reduction of Scour around a Rectangular Bridge Pier Located in the 180 Degree Sharp Bend. سامانه نشریات, 1396; 3(2): 32-46. doi: 10.22055/jhs.2018.24900.1065

Experimental Study of the Effect of Base-level fall at the Beginning of the Bend on Reduction of Scour around a Rectangular Bridge Pier Located in the 180 Degree Sharp Bend

Journal of Hydraulic Structures
مقاله 4، دوره 3، شماره 2 - شماره پیاپی 6، اسفند 2017، صفحه 32-46    اصل مقاله (1.1 M)
نوع مقاله: Research Paper
شناسه دیجیتال (DOI): 10.22055/jhs.2018.24900.1065
نویسندگان
Mohammad vaghefi* ؛ Mohammad moghanloo؛ Danesh Dehghan؛ Arsalan keshavarz
Department of Civil Engineering, Faculty of Engineering, Persian Gulf University, Bushehr, Iran.
چکیده
Base-level fall in river beds occurs due to varying natural or unnatural causes. Base-level fall causes the change in the behavior of flow at the location of drop in base-level. In such situations, most of scour occur at the foot of the slope, and slope wall retreats in the upstream direction. This phenomenon widens the wall of the river bank, thus leading to its destruction. The amount of bed topography variations and scour around a rectangular bridge pier with an oblong nose located in the 90 degree angle of a 180 degree sharp bend was studied in this work by generating base-level fall at the beginning of the 180 degree sharp bend, and it was compared with a case without a base-level fall. The results indicated that in the case of base-level fall at the upstream side of the bridge pier, increase in flow depth, as well as reduction in velocity at the area around the pier, is observed, and the maximum depth of scour hole and the volume of scour hole around the pier respectively reduce by 73 and 97% in comparison with those in the case where no base-level fall occurs.
کلیدواژه‌ها
180 Degree Sharp Bend؛ base-level fall؛ Scour؛ Bridge pier؛ Topography
مراجع
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