IJE TRANSACTIONS A: Basics Vol. 32, No. 1 (January 2019) 36-45    Article in Press

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N. Shahbazi, S. Tariverdilo and A. Amani Dashlejeh
( Received: November 13, 2018 – Accepted in Revised Form: January 03, 2019 )

Abstract    Geometric imperfections such as radial imperfection, diamond shape, and local dimples could affect the buckling mode and load carrying capacity of axially compressed steel tubular columns. This paper experimentally investigates the effect of radial imperfection on the load carrying capacity of tubular columns. Test samples include 100 specimens with different values for diameter, length, thickness, imperfection amplitude and imperfection location. Considering applications of columns in buildings, bridges, and offshore jackets, diameter to thickness and slenderness ratios were varied between 20-90 and 17-181, respectively. Results showed that depending on the slenderness ratio and the severity of the imperfection, there was a significant difference between buckling loads of perfect and imperfect specimens.


Keywords    Column, Steel Structures, Radial Imperfection, Load Capacity, Buckling



ناکاملی¬های هندسی همچون ناکاملی شعاعی، الماسی شکل و گودافتادگی موضعی می¬¬توانند بر مود کمانش و ظرفیت باربری ستونهای جدارنازک تحت بارهای فشاری محوری تاثیرگذار باشند. این مقاله اثر ناکاملی شعاعی بر ظرفیت باربری ستونهای جدارنازک را به طور آزمایشگاهی مورد بررسی قرار می¬دهد. با توجه به کاربرد ستونها در ساختمانها، پلها و سازه¬های دریایی، نسبت قطر به ضخامت و لاغری به ترتیب بین 20 تا 90 و 17 تا 181 در نظر گرفته شده است. نتایج نشان می¬دهد که بسته به نسبت لاغری و شدت ناکاملی، تفاوت عمده¬ای بین ظرفیت کمانشی ستونهای کامل و ناکامل وجود دارد.


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