بررسی عمق آبشستگی نهایی اطراف پایه پل با استفاده از ترکیب طوقه و شکاف و طناب سیمی
محورهای موضوعی : برگرفته از پایان نامهمیلاد مرناض 1 , سید امین اصغری پری 2 , محمود شفاعی بجستان 3
1 - دانشجوی کارشناسی ارشد سازههای هیدرولیکی دانشگاه صنعتی خاتم الانبیاء بهبهان
2 - دانشیار دانشگاه صنعتی خاتم الانبیاء بهبهان،
3 - استاد دانشگاه شهید چمران اهواز
کلید واژه: آبشستگی, پایه پل, طوقه, شکاف, کابل,
چکیده مقاله :
از عوامل عمده تخریب پل‌ها می توان به آبشستگی موضعی اطراف پایه‌های پل اشاره کرد . لذا برای کنترل این پدیده مطالعاتی صورت گرفته که روش هایی برای محافظت پایه‌ها ابداع گردیده است. از جمله روش‌های موثر می توان به استفاده از نصب طوقه ، کابل و ایجاد شکاف در پایه اشاره نمود. از انجایی که ایجاد شکاف در پایه پل هم از لحاظ اجرایی و هم از نظر بهره برداری مشکلاتی را ایجاد می کند و نیز اثر کابل پیچی دور پایه‌ها نیز اثر نسبتا کمی در کاهش آبشستگی دارد ، لذا در این تحقیق به صورت آزمایشگاهی به بررسی اثر روکش‌های شکاف‌دار و مارپیچ‌دار و طوقه‌های دندانه دار که از ترکیب طوقه و کابل و شکاف ایجاد شده در طوقه به وجود آمده‌اند، بر میزان عمق آبشستگی پایه پل‌ها پرداخته شده است ، که در بهترین حالت طوقه‌های دندانه‌دار توانستند به مقدار 83 درصد حداکثر عمق آبشستگی را اطراف پایه کاهش دهد .
The local scour around the piers is an important factor that causes of the destruction of the bridges. Therefore, to avoid this phenomenon there is scientific solutions to protect the pier against scour. some of the most effective techniques you can use ,are using the collars or threading or slots on the pier. Therefore using the slots is not practical or not suitable to consider as permanent solution and threading is not so effective method so there is an idea to compose threading and slots with collars together in this experimental work that can make slots and threading so more practical and useful in pier scour reduction . there have been created some new tools which name jet-collar , slot-veneer and thread-veneer. at the best condition results shows that some of the collars which have a jagged side as a jet and a collar at other side , so this jet-collar could reduce local scour by 83% at pier side.
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