محاسبه محل بهینه مهارهای بازویی در سازه با مینیمم کردن لنگر پای هسته تحت بار جانبی

نوع مقاله : مقاله پژوهشی

نویسنده

دانشگاه آزاد اسلامی واحد تربت جام، تربت جام، ایران

چکیده

یکی از مشکلات اساسی در سازه ­های بلند مقابله با نیروی جانبی و در نتیجه جابجایی زیاد ایجاد شده تحت اثر این نیروها به ویژه در طبقات بالای سازه و همچنین افزایش لنگر پای سازه می­ باشد. یکی از سیستم­ هایی که در سازه ­های بلند برای مقابله با این نیروها و جابجایی­ ایجاد شده به وسیله این نیروها مورد استفاده قرار می­گیرد، استفاده از مهاربازویی است. در این سیستم هسته مرکزی به وسیله یک یا چند مهاربازویی به ستون­ های کناری متصل می­ شود. در این تحقیق به بررسی موقعیت بهینه مهارهای بازویی تحت بارگذاری همزمان مثلثی- متمرکز و بارگذاری باد با در نظر گرفتن چهار مهاربازویی در سازه و اثر تغییرات سختی المان ­­های سازه بر روی کاهش لنگر پای سازه پرداخته شده است. همچنین بازدهی کاهش حداکثر لنگر ایجاد شده در سازه دارای مهارهای بازویی در مقایسه با سازه بدون مهاربازویی مورد مقایسه قرار گرفته است. نتایج نشان دهنده آن است که با افزایش سختی مهارهای بازویی محل بهینه مهارهای بازویی به سمت پایین سازه جابجا خواهد شد و همچنین فاصله مهارهای بازویی از یکدیگر کاهش می­ یابد. محل بهینه مهارهای بازویی هنگامی که شدت بارگذاری باد افزایش یابد، به سمت بالای سازه جابجا خواهد شد. همچنین فاصله مهارهای بازویی در این حالت از یکدیگر افزایش خواهد یافت.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Optimal position of outriggers for minimizing the base moment under lateral load

نویسنده [English]

  • sajjad Baygi
Department of civil engineering/Islamic Azad University of Torbate jam
چکیده [English]

In this paper, the optimum position of Outriggers in a structure for minimizing the base moment under lateral loads is investigated. To do so, the base moment and top story displacement are formulated. Then, a Matlab code is employed to find the optimum positions of the Outriggers. Different kinds of lateral loads including concentrated, uniform, triangular and a combination of such loads are taken into account. Moreover, the effects of the variation of structural elements such as columns, Outriggers and core on the base moment and top story displacement are examined. The outcomes indicated that the optimum points of Outriggers get closer when the flexural rigidity of Outriggers increases. Furthermore, it is shown that the greatest decrease in the base moment occurs in a specific range which depends on the structure parameters such as axial rigidity of columns, the distance of columns, the flexural rigidity of Outriggers and height of the structure. The results show that when the wind load intensity increases, the optimum position of the Outriggers will move to the top of the structure.

کلیدواژه‌ها [English]

  • Optimum Location
  • High-rise Building
  • Outrigger
  • Base moment
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