بررسی عددی و آزمایشگاهی آبشستگی در اطراف گروه پایه کج توأم با طوق و مواد نانو رس

نویسندگان

1 دانشیار گروه مهندسی آب، دانشکده کشاورزی، دانشگاه تبریز

2 دانشجوی دکتری سازه‌های آبی، دانشکده کشاورزی، دانشگاه تبریز

3 استاد گروه مهندسی آب، دانشکده کشاورزی، دانشگاه تبریز

چکیده

در رودخانه­ها سازه­های هیدرولیکی به صورت مانعی در برابر جریان آب قرار دارند و الگوی جریان در نزدیکی خود را تغییر داده و به صورت موضعی باعث آبشستگی در اطراف سازه می­شوند. آبشستگی پایه پل از پدیده­های مهم در هیدرولیک رسوب بوده که در اثر آن حفره­ای در اطراف پایه به­وجود می­آید و پایداری آن را تضعیف می­کند. روش­های مختلفی برای جلوگیری یا کاهش آبشستگی موضعی ارائه شده است که در این تحقیق تأثیر طوق، مواد نانورس و زاویه پایه پل در گروه پایه­ها مورد مطالعه واقع شده است. نتایج نشان می­دهد پایه پل با زاویه 15 درجه بیشترین کاهش عمق حفره آبشستگی را دارا می­باشد. بررسی­ها بیانگر آن است که در گروه پایه­ها با زاویه کج­شدگی 15 درجه کاهش 14 درصدی حفره آبشستگی و در حالت طوق دار کاهش 86 درصدی وجود دارد. هم­چنین با استفاده از مواد نانورس عمق حفره آبشستگی در حالت بدون طوق 5/18 درصد کاهش یافته است.

کلیدواژه‌ها


عنوان مقاله [English]

Numerical and Experimental Investigation of Local Scour around Inclined Pier Group with Collar and Nanostructures

نویسندگان [English]

  • Hadi Arvanaghi 1
  • Fatemeh Jafari 2
  • Akram Abbaspour 3
  • Ali Hosseinzadeh Dalir 3
1 Assoc. Prof., Dept. of Water Engineering, Agric., Univ. of Tabriz, Iran
2 Ph.D. Student of Water Struc., Faculty of Agric., Univ. of Tabriz, Iran
3 Prof., Dept. of Water Engineering, Agric., Univ. of Tabriz, Iran
چکیده [English]

Hydraulic structures situated as an obstacle in front of water flow that changed the flow pattern in their vicinity and causing the local scour around the structure. The scour around the bridge pier is one of the most important phenomena in sediment hydraulics, which creates a hole around the pier and undermines its stability. Different methods have been proposed to prevent or reduce the local scour. In this study, the effects of collars, nanoclay materials and angle of piers have been studied in pier group. The results show that for the pier with the angle of 15 degree was observed the greatest decrease in the depth of the scour hole. Studies show that in the group pier with inclination angle of 15 degrees, there was 14 percent scour hole reduction and with presence of a collar the reduction of scour hole was 86 percent. Also, by using nanoclay materials, the depth of the scour hole in the without collar condition was reduced by 18.5%.

کلیدواژه‌ها [English]

  • Collar
  • Inclined pier group
  • Nanoclay
  • Numerical model
  • Scour
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