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FİBER KOMPOZİT ÇOK KATLI TÜPSEL SİLİNDİRLERİN BURULMA EKSENEL BASKI YÜKÜ VE DIŞ BASINÇ YÜKLEMELERİ ALTINDA BURKULMA DENKLEMLERİNİN ÇIKARILIŞLARI

Bu çalışmada, çok katlı fiber kompozit silindirlerin denge denklemleri aynı anda etkiyen burulma, eksenel yük ve dış basınç yüklemeleri altında burkulma analizi için incelenmiştir. Denge denklemleri, Klasik ve Birinci Mertebeden Kayma Deformasyon Teorilerine göre olmak üzere her ikisi içinde, iki grup çıkarımlarda matris formunda elde edilmişlerdir. Bu denklemlerin her birinde, başlangıç gerilme yüklemelerinin etkisi dikkate alınmıştır. Bütün bu ifadeler, üç değişik yüklemenin aynı anda etkidiği fiber kompozit silindirin dengedenklemleridir. Daha önce tanımlanmış olan iki ana teoriye göre çözümleme yapabilmek için, yerdeğiştirmeler cinsinden elde edilen denge denklemleri ilgili yaklaşık seri açılımları ile birlikte kullanılarak tanımlanmışlardır. Elde edilen ifadeler, özdeğer probleminin sıkıştırılmış matris formunu veren şekliyle görülmüşlerdir.

Anahtar Kelimeler:

Burkulma, ortotropik, fiber kompozit, denge denklemleri, özdeğer-problemi, silindir

DERIVATIONS OF BUCKLING EQUATIONS FOR THE MULTILAYERED FIBER COMPOSITE TUBULAR CYLINDERS UNDER TORSION AXIAL COMPRESSIVE LOAD AND EXTERNAL PRESSURE

In this study, equilibrium equations of multi-layered fiber composite cylinders under combined torsion, axial force and external pressure were examined for buckling analysis. Equations of equilibrium were obtained for both Classical and First Order Shear Deformation Theories in the two groups of derivations as matrix equation. In each of these equations, initial stress loading was included. All of these expressions are the equilibrium equations of fiber composite cylinder in which the three different type of loadings are acting simultaneously. In order to obtain the solutions corresponding to the previously described two main theories, displacement based equilibrium equations have been used by defining them with the related approximated series expansions. Equations appeared to be seen in the compressed matrix form of an eigenvalue problem.

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