روش رهایی پویا برای محاسبه بار کمانشی قاب‌ها

نوع مقاله : مقاله کامل پژوهشی

نویسندگان

گروه مهندسی عمران، دانشکده مهندسی، دانشگاه آزاد اسلامی، واحد مشهد

چکیده

محاسبه بار کمانشی سازه­ها با شیوه­های کلاسیک و بررسی دترمینان ماتریس سختی دشوار است. در این مقاله، روش رهایی پویای صریح برای تعیین بار کمانشی قاب­ها به کار می­رود. نخست، چگونگی محاسبه بار کمانشی با روش­های متداول بیان می­شود. سپس، شیوه رهایی پویا و رابطه­های آن معرفی می­گردند. در ادامه، راهکار نوینی بر پایه نمودار بار- تغییر مکان روش رهایی پویا برای محاسبه نخستین بار کمانشی سازه­ها پیشنهاد می­شود. برای نشان دادن توانایی شیوه پیشنهادی در محاسبه بار کمانشی، چندین سازه شامل ستون­ها و قاب­های دو بعدی تحلیل غیرخطی هندسی می­شوند. نتایج عددی کارایی مناسب شیوه رهایی پویا را در تعیین بار کمانشی نشان می­دهد، به گونه­ای که کوچک­ترین بار کمانشی سازه به صورت ساده در دسترس قرار می­گیرد.

کلیدواژه‌ها


عنوان مقاله [English]

Dynamic Relaxation Method for Calculating Buckling Load of Frames

نویسندگان [English]

  • Javad Alamatian
  • Seyed mohammad Hosseininezhad Goshik
Faculty of Engineering, Mashhad Branch, Islamic Azad University, Mashhad
چکیده [English]

In the present paper, an explicit algorithm is developed for calculating buckling load of frames. Here, the modified Dynamic Relaxation method is utilized so that the first structural buckling load is achieved.

کلیدواژه‌ها [English]

  • Dynamic Relaxation (DR)
  • Buckling load
  • Vector operation
  • Frame structures
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