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

Öz

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.

Anahtar Kelimeler

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

Kaynakça

1. [1] B. G. Falzon, “The behaviour of damage tolerant hat-stiffened composite panels loaded in uniaxial compression,” Compos. Part A Appl. Sci. Manuf., vol. 32, no. 9, pp. 1255–1262, 2001, doi: https://doi.org/10.1016/S1359-835X(01)00074-4.
2. [2] B. G. Prusty, “Free vibration and buckling response of hat-stiffened composite panels under general loading,” Int. J. Mech. Sci., vol. 50, no. 8, pp. 1326–1333, 2008, doi: https://doi.org/10.1016/j.ijmecsci.2008.03.003.
3. [3] A. Nagesh, O. Rashwan, and M. Abu-Ayyad, “Optimization of the Composite Airplane Fuselage for an Optimum Structural Integrity.” Nov. 09, 2018. doi: 10.1115/IMECE2018-88215.
4. [4] E. G. Koricho and G. Belingardi, “An experimental and finite element study of the transverse bending behaviour of CFRP composite T-joints in vehicle structures,” Compos. Part B Eng., vol. 79, pp. 430–443, 2015, doi: https://doi.org/10.1016/j.compositesb.2015.05.002.
5. [5] W. Hou, X. Xu, H. Wang, and L. Tong, “Bending behavior of single hat-shaped composite T-joints under out-of-plane loading for lightweight automobile structures,” J. Reinf. Plast. Compos., vol. 37, no. 12, pp. 808–823, Apr. 2018, doi: 10.1177/0731684418764608.
6. [6] W. Hou, X. Xu, X. Han, H. Wang, and L. Tong, “Multi-objective and multi-constraint design optimization for hat-shaped composite T-joints in automobiles,” Thin-Walled Struct., vol. 143, p. 106232, 2019, doi: https://doi.org/10.1016/j.tws.2019.106232.
7. [7] S. Mesmoudi, M. Rammane, Y. Hilali, O. Askour, and O. Bourihane, “Variable RPIM and HOCM coupling for non-linear buckling and post-buckling analysis of transverse FG sandwich beams,” Structures, vol. 53, pp. 895–907, 2023, doi: https://doi.org/10.1016/j.istruc.2023.04.103.
8. [8] P. Hao, K. Zhang, D. Liu, X. Wang, S. Feng, and B. Wang, “Intelligent design and buckling experiment of curvilinearly stiffened thin-walled structures,” Int. J. Solids Struct., vol. 293, p. 112737, 2024, doi: https://doi.org/10.1016/j.ijsolstr.2024.112737.

9. [9] S. Nadeem Masood, S. R. Viswamurthy, and K. M. Gaddikeri, “Composites airframe panel design for post-buckling – An experimental investigation,” Compos. Struct., vol. 241, p. 112104, 2020, doi: https://doi.org/10.1016/j.compstruct.2020.112104.
10. [10] X. Liu, K. Han, R. Bai, Z. Lei, and H. Wang, “Buckling measurement and numerical analysis of M-type ribs stiffened composite panel,” Thin-Walled Struct., vol. 85, pp. 117–124, 2014, doi: https://doi.org/10.1016/j.tws.2014.08.008.
11. [11] Y. Wang, F. Wang, S. Jia, and Z. Yue, “Experimental and numerical studies on the stability behavior of composite panels stiffened by tilting hat-stringers,” Compos. Struct., vol. 174, pp. 187–195, 2017, doi: https://doi.org/10.1016/j.compstruct.2017.04.039.
12. [12] W. Hou, X. Xu, L. Sang, and L. Tong, “Failure of single hat-shaped thin-walled tubular composite T-joints under impact loading,” Thin-Walled Struct., vol. 154, p. 106815, 2020, doi: https://doi.org/10.1016/j.tws.2020.106815.
13. [13] Y. Mo, D. Ge, and B. He, “Experiment and optimization of the hat-stringer-stiffened composite panels under axial compression,” Compos. Part B Eng., vol. 84, pp. 285–293, 2016, doi: https://doi.org/10.1016/j.compositesb.2015.08.039.
14. [14] M. Albayrak, M. O. Kaman, and I. Bozkurt, “Experimental and Numerical Investigation of the Geometrical Effect on Low Velocity Impact Behavior for Curved Composites with a Rubber Interlayer,” Appl. Compos. Mater., vol. 30, no. 2, pp. 507–538, 2023, doi: 10.1007/s10443-022-10094-5.
15. [15] “ANSYS Academic Release 2020, Workbench Material Library.”