İnce Duvarlı Kirişlerde Eğrilik Yarıçapının Burkulma Yükü Üzerindeki Etkisinin Araştırılması

Öz

Bu çalışmada, yüksek mukavemet-ağırlık oranları nedeniyle havacılık, otomotiv ve yapı mühendisliğinde yaygın olarak kullanılan ince cidarlı kirişlerin burkulma davranışı üzerinde eğrilik yarıçapının etkisi incelenmektedir. İnce cidarlı şapka şeklindeki yapılar için kritik bir hasar modunu temsil eden burkulma olgusu, sayısal yöntemlerin kullanımıyla eksenel yükleme altında incelenmiştir. Değişen eğrilik açılarına ve aynı boyutlara sahip üç farklı geometriyi modellemek için ANSYS Workbench kullanılarak doğrusal olmayan bir analiz yürütülmüştür. Modeller, 1 mm'lik bir yer değiştirmede kritik burkulma yüklerini ve tepki kuvvetlerini belirlemek amacıyla analize tabi tutulmuş, özellikle doğrusal olmayan ve burkulma sonrası davranışa odaklanılmıştır. Yapısal uygulamalardaki önemi göz önüne alındığında, malzeme olarak Alüminyum Alaşım NL seçilmiştir. Özdeğer burkulma analizi, ilk on mod için kritik yükleri belirlemiş ve daha yüksek eğrilik açılarına sahip modellerin daha kararlı burkulma özellikleri gösterdiğini, daha küçük açılara sahip olanların ise yerel deformasyona daha yatkın olduğunu ortaya koymuştur. Bu yapıların doğrusal olmayan yük taşıma kapasitelerini belirlemek için burkulma sonrası analiz yapılmıştır.

Anahtar Kelimeler

• burkulma
• ince cidarlı kiriş
• burkulma sonrası
• sonlu elemanlar analizi

Investigation of The Effect of Radius of Curvature on Buckling Load in Thin-Walled Beams

Abstract

This study examines the effect of curvature radius on the buckling behavior of thin-walled beams, which are commonly used in aerospace, automotive, and structural engineering due to their high strength-to-weight ratios. The buckling phenomenon, which represents a critical failure mode for thin-walled hat-shaped structures, was investigated under axial loading through the utilization of numerical methods. A nonlinear analysis was conducted using ANSYS Workbench to model three distinct geometries with varying curvature angles and identical dimensions. The models were subjected to analysis in order to ascertain the critical buckling loads and reaction forces at a displacement of 1 mm, with a particular focus on both nonlinear and post-buckling behavior. Given its importance in structural applications, Aluminum Alloy NL was selected as the material. The eigenvalue buckling analysis identified the critical loads for the first ten modes, revealing that models with higher curvature angles demonstrated more stable buckling characteristics, whereas those with smaller angles were more prone to local deformation. A post-buckling analysis was conducted to ascertain the nonlinear load-bearing capacities of these structures.

Keywords

• buckling
• thin-walled beam
• post-buckling
• finite element analysis

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