تحلیل پاسخ دینامیکی سازه های بلند تحت تأثیر نیروی محوری

نوع مقاله : پژوهشی

نویسندگان

دانشگاه فردوسی مشهد

چکیده

در این تحقیق، معادلات انتگرالی تضعیف شده جهت محاسبه فرکانس های طبیعی ارتعاش سازه های بلند دارای جرم و سختی متغیر در ارتفاع و تحت تأثیر نیروی محوری ارائه شده است. معادله دیفرانسیل حاکم بر ارتعاش آزاد یک تیر کنسول غیرمنشوری با سختی برشی و سختی خمشی و تحت تأثیر نیروی محوری، از طریق چهار مرتبه انتگرال گیری پی در پی به فرم تضعیف شده ی آن تبدیل شده است. با تقریب تابع مد شکل ارتعاش توسط یک سری توانی، معادله انتگرالی به یک دستگاه معادلات جبری خطی تبدیل شده است. در نهایت با محاسبه جواب غیر بدیهی دستگاه معادلات ، فرکانس های طبیعی ارتعاش سازه بلند بدست آمده است. سازه مورد نظر در نرم افزار SAP-2000 مدل سازی شده و نتایج تحلیل به کمک روش ارائه شده، نتایج مدل سازی در نرم افزار و همچنین نتایج بدست آمده از روشهای سایر محققین با یکدیگر مقایسه شده است.

کلیدواژه‌ها


عنوان مقاله [English]

Dynamic Response Analysis of Tall Buildings under Axial Force Effects

نویسندگان [English]

  • mehrdad mohammadnejad
  • hasan haji kazemi
-
چکیده [English]

In this paper, weak form integral equations is presented for dynamic response analysis of tall structures with variable stiffness and mass along the height under axial force. Through repetitive integration, the governing differential equation is converted into its weak form integral equation. The tall structure is modeled by a non-prismatic cantilever beam. By approximation of the mode shape function by a power series, the integral equation is converted into a system of linear algebraic equations. The natural frequencies of tall structure are calculated by determination of a non-trivial solution for system of equations. The analysis results are compared by those obtained from SAP-2000 software and other available references.

کلیدواژه‌ها [English]

  • Tall Structure
  • Shear-Bending beam
  • Weak form integral equation
  • Axial force
  • Natural Frequency
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