تجزیه و تحلیل دینامیکی مخازن آب بتن آرمه تحت اثر انفجار با در نظر گرفتن اندرکنش آب و سازه

نوع مقاله : مقاله پژوهشی

نویسندگان

Unit94, Entrance2, Block14, Phase2, Ekbatan

چکیده

با توجه به گسترش حملات تروریستی در سراسر دنیا و احتمال هدف قرار دادن سازه‌های مختلف، مبحث پدافند غیرعامل اهمیت فراوانی یافته است. یکی از این سازه‌ها ، مخازن ذخیره‌ای آب می‌باشد که در برابر انفجار بسیار آسیب‌پذیر بوده و با تخریب این نوع از سازه‌ها ممکن است از نقطه‌نظر بعدهای انسانی، اقتصادی و زیست‌محیطی گاها جبران‌ناپذیر باشد. هدف از این پژوهش، بررسی اثر انفجار بر روی تنش‌های حلقوی و تغییر مکان‌های ایجادشده بر روی بدنه مخزن بتن مسلح استوانه‌ای روزمینی ذخیره آب ناشی از نیروهای هیدرودینامیکی با در نظر گرفتن میزان پرشدگی آب و ابعاد مخازن می‌باشد. همچنین با توجه به فواصل 5 و 10 متر از مرکز انفجار، تنش‌های حلقوی ایجادشده در بدنه مخازن بررسی می‌شود. برای این منظور از نرم‌افزار تجاری آباکوس برای شبیه‌سازی عددی سه مخزن با ارتفاع‌های 4، 6 و 8 متری و شعاع ثابت 3 متر با درصد پرشدگی  0، 25 ، 50 ، 75 و 100  از آب استفاده شده است. نتایج کار نشان داده است که با افزایش درصد پرشدگی آب سختی مخزن افزایش پیدا کرده و سبب شده تغییر مکان بدنه یک کاهش 25/31 درصدی برای مخزن کاملاً پر نسبت به مخزن خالی داشته باشد. همچنین پرشدگی آب سبب شده تا حساسیت مخازن در برابر ناپایداری کاهش یابد. نتایج نشان داده است که تنش‌های حلقوی بدنه مخزن، تحت تأثیر امواج انفجار از خارج و فشار آب از داخل قرار دارد به‌طوری‌که وجود آب در مخزن سبب شده تا تنش‌های حلقوی در بدنه   حدود 20 مگاپاسکال  افزایش پیدا کند.

کلیدواژه‌ها


عنوان مقاله [English]

Dynamic Analysis of RC Water Tanks under Explosion by Consideration Water-Structure Interaction

نویسندگان [English]

  • Majid Moghadam
  • SeyedVahid RazaviTosee
  • mehrdad Shahrbanouzadeh
Unit94, Entrance2, Block14, Phase2, Ekbatan
چکیده [English]

The issue of passive defense has become very important due to the increase of terrorist attacks around the world and the possibility of targeting various structures. One of these structures is water storage tanks which are very vulnerable to explosion and the destruction of this type of structure may be irreparable from in term of human, economic, and environmental parameters. The purpose of this study is to investigate the effect of the explosion on cyclic stresses and displacement created on the body of a cylindrical reinforced concrete tank with water storage due to hydrodynamic forces by considering the amount of water filling and the dimensions of the tanks. Also, according to the distances of 5 and 10 meters from the center of the explosion, the cyclic stresses created in the body of the tanks are investigated. For this purpose, Abacus commercial software has been used to numerically simulate three tanks with heights of 4, 6, and 8 meters and a fixed radius of 3 meters with a filling percentage of 0, 25, 50, 75, and 100 of water. The results show that with increasing the percentage of water filling, the hardness of the tank has increased and has caused the displacement of the body to have a decrease of 31.25% for a fully filled tank compared to an empty tank. Water filling also reduces the sensitivity of tanks to instability. The results show that the cyclic stresses of the tank body are affected by blast waves from the outside and water pressure from the inside so that the presence of water in the tank has caused the cyclic stresses in the body to increase by about 20 MPa.

کلیدواژه‌ها [English]

  • Dynamic response
  • water tanks
  • Explosion Loading
  • hydrodynamic force
  • Water-Structure Interaction
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