تحلیل رفتار مهار بازویی میراشده در سازه های بلند به روش فوریه در فضای هیلبرت

نوع مقاله : مقاله کامل پژوهشی

نویسندگان

1 گروه عمران، دانشکده فنی و مهندسی، دانشگاه بین‌المللی امام خمینی (ره) قزوین

2 گروه عمران، دانشکده فنی و مهندسی، دانشگاه بین المللی امام خمینی (ره) قزوین

چکیده

     یکی از مهم­ترین پارامترهای کنترل‌کننده طراحی در سازه ­های بلند، تغییر مکان جانبی سازه می ­باشد. انواع مختلف سیستم ­های مقاوم سازه­ای جهت تحمل بارهای جانبی و ثقلی پیشنهاد شده است، که در این میان، سیستم هسته مرکزی با مهار بازویی و میراگر ویسکوز (The central core system with outrigger and viscous damper) نقش قابل‌ملاحظه‌ای در کاهش لنگر واژگونی و بهبود معیارهای عملکردی سازه دارد. هسته مرکزی به خاطر جرمش در اثر شتاب جاذبه زمین تحت بار محوری قرار می­ گیرد. در پژوهش­ های قبلی اثر توأم نیروی محوری و سختی ستون­ های پیرامونی بر ارتعاشات سیستم موردنظر لحاظ نشده است. در این پژوهش ارتعاشات آزاد و اجباری سیستم هسته مرکزی به انضمام مهاربند بازویی و میراگر ویسکوز، با لحاظ نیروی محوری ناشی از جرم هسته مرکزی مورد بررسی قرار می­ گیرد. با توجه به مختلط بودن مقادیر ویژه و غیر متعامد بودن بردارهای ویژه این سیستم و برای دستیابی به پاسخ سیستم، از تکنیک متعامدسازی بردارهای ویژه در فضای هیلبرت (Hilbert Space) و بسط سری فوریه براساس بردارهای حاصل استفاده می­ شود. نتایج حاصل نشان می‌دهد که لحاظ اثر نیروی محوری باعث افزایش جابه ­جایی نسبی طبقات، برش پایه و لنگرپایه می­ شود.

کلیدواژه‌ها


عنوان مقاله [English]

Analysis of Behavioral Damped Outrigger in Tall Structures by Fourier Method in Hilbert Space

نویسندگان [English]

  • Amirhossein Taherkhani 1
  • Majid Amin Afshar 2
1 Department of Civil Engineering, Imam Khomeini International University, Qazvin, Iran
2 Department of Civil Engineering, Imam Khomeini International University, Qazvin, Iran
چکیده [English]

Achieving efficient methods to protect the structure against forces such as wind and earthquake is one of the first steps in the design of structures and has led to the provision of structural control systems. Structural control systems include three systems, active control, passive control and semi-active control. (Spencer Jr et al. 2003), (Mulligan et al. 2007). The outrigger system with the viscous damper, was proposed by, (Gamaliel, 2008) and its effect on tall structures was investigated, (O'Neill, 2006) showed that the use of damper and increasing damping in the outrigger system in proportion to increasing the stiffness and dimensions of the structure. (Farzad et al. 2019) has also used ultrasonic algorithms to determine the optimal position of outrigger system in tall steel frames. Experimental and analytical researches also show that the use of outrigger system is effective in reducing the lateral displacement of tall structures. (Tan et al. 2012), (Deng et al. 2014).
(Jovanovich, 2011) Used the Fourier series method in Hilbert space to investigate the transverse vibrations of the beam with boundary conditions of linear viscosity.
In this paper, the vibrations of the structure and the effect of central core system with the damped arm brace using axial load (due to the mass of the central mass) in the control of lateral displacement due to harmonic loading are investigated. Previous studies have not considered the effect of perimeter columns stiffness and the effect of axial force on frequencies and lateral displacement of the structure, and for solving the partial differential equation governing the problem, the Fourier series method is used to define the differential operator in Hilbert space.

کلیدواژه‌ها [English]

  • Tall structure
  • Structural control
  • Structural dynamics
  • Outrigger-braced
  • Hilbert space
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