بررسی آزمایشگاهی و عددی میراگر اصطکاکی ترکیبی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 موسسه آموزش عالی غیر انتفاعی غیر دولتی سراج/ تبریز/ ایران

2 موسسه آموزش عالی غیرانتفاعی غیر دولتی سراج

چکیده

در این مقاله به معرفی و بررسی عددی و آزمایشگاهی میراگر اصطکاکی ترکیبی جدید موسوم به HFDپرداخته شده است. این میراگر ترکیب سری دو میراگر اصطکاکی با دو سطح نیروی لغزش (فیوز اصلی و کمکی) متفاوت است که قادر به اتلاف انرژی متناسب با دو سطح زمین لرزه‌ی متوسط و شدید می‌باشد. چهار نمونه‌ی آزمایشگاهی مطابق با ساختار پیشنهادی، تحت بارگذاری چرخه ای قرار گرفته است. نتایج منحنی‌های نیرو تغییر مکان نشان می‌دهد هندسهی پیشنهاد شده می‌تواند به خوبی عملکرد دوسطحی را فراهم کند، به نحوی که تا قبل از تغییر مکان گپ تنها میراگر کمکی و بعد از آن ترکیب هر دو میراگر باعث اتلاف انرژی می‌شوند. سپس ویژگی‌های نیرو-جابه جایی، انرژی اتلافی و میرایی ویسکوز معادل برای چرخه‌های متوالی بارگذاری محاسبه شد و مشخص گردید که این مقادیر به لحاظ مطابقت با الزامات SEI41-06/ASCIبرای دستگاه‌های وابسته به جابه جایی، واجد شرایط می‌باشد. مقایسه انرژی جذب شده در نمونه ها نشان داد در بازه‌های تغییر مکانی بزرگ تر از تغییر مکان گپ، فرآیند جذب انرژی در چرخه‌های بارگذاری متناظر با این تغییر مکان‌ها بهبود یافته است. در ادامه با استفاده از ابزار مدل سازی Open Sees تعداد 10 مدل ساخته شدند و تطابق خوبی بین نتایج آزمایشگاهی و عددی به دست آمد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental and Numerical Study of Hybrid Friction Damper

نویسندگان [English]

  • Elham Moaddab 1
  • babak shahbazi 2
1 Seraj higher education institute/ Tabriz/ Iran
2 Seraj higher education institute, Tabriz, Iran
چکیده [English]

In this study, a new hybrid energy dissipation device was developed by combining two friction dampers (auxiliary and main fuse) in series to be used for seismic control of two different earthquake intensities. Compared with the conventional friction dampers, the new hybrid damper has an advantage in which only auxiliary fuse (with low sliding force) is activated for moderate earthquakes and both fuses work simultaneously for strong earthquakes. Cyclic loading tests of the combined hybrid dampers were carried out in order to evaluate their seismic energy dissipation capability. The obtained experimental force-displacement indicated proper details of the new damper to create two performance level. Finite element analyses of the test specimens were also carried out for comparison, which had good agreement with the test results. Force displacement characteristics, Energy dissipation and equivalent viscous damping were also derived and good agreement has been found with code requirement for displacement dependent dampers. Also, it was demonstrated that engaging the main fuse with non-loaded pretention bolts, strength losses of the hybrid damper in subsequent cycles were limited compared to the common friction dampers which can be called “resurrection-type” behavior of the main fuse in the main shocks.

کلیدواژه‌ها [English]

  • friction damper
  • hybrid damper
  • moderate earthquake
  • energy dissipation
  • experimental sample
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