TABAKALI KOMPOZİT KİRİŞLERİN EĞİLME ANALİZİ

Yıl 2020, Sayı: 001, 19 - 33, 30.06.2020

Mustafa Haluk Saraçoğlu Mustafa Emin Gürlek

Öz

Bu çalışmada; tabakalı kompozit kirişlerin gerilme ve şekil değiştirme analizleri sonlu farklar yöntemi kullanılarak yapılmıştır. Analizlerde farklı mesnet koşulları ve farklı yüklemeler etkisi altındaki kirişler, Euler-Bernoulli ve Timoshenko kiriş teorilerine göre incelenmiştir. İncelenen bu kirişler farklı tabaka sayıları ve farklı oryantasyon açılarına sahiptirler. Tabakalı kompozit kirişler, düzlem gerilme problemi olarak ele alınmıştır. Gerilme ve şekil değiştirme analizleri yapılırken ilgili bünye bağıntıları ve denge denklemleri için bazı kabuller yapılmıştır. Üç boyutlu doğrusal olmayan şekil değiştirme ifadeleri, iki boyutlu ve doğrusal şekil değiştirme ifadelerine indirgenmiştir. Bu diferansiyel denklemlerin çözümü için merkezi sonlu fark ifadeleri kullanılmıştır. Her sonlu fark düğüm noktası için merkezi sonlu fark ifadesi yazılmıştır. Daha sonra bu ifadeler sınır şartlarına göre tekrar düzenlenmiştir. Elde edilen bünye bağıntıları ve denge denklemlerinin çözümü için açık kaynak kodlu olan DEV-C++ V 5.8.3 editörü kullanılarak bir bilgisayar programı geliştirilmiştir. Geliştirilen bu program kullanılarak sayısal uygulamalar yapılmıştır. Literatürde bulunan örnek problemler çözülerek geliştirilen bilgisayar programının doğruluğu test edilmiştir.Sonuç olarak tabaka dizilişleri ve sınır şartları farklı tabakalı kompozit kirişlerin yük altındaki gerilme ve şekil değiştirme davranışları ortaya konulmuştur. Elde edilen sonuçlar tablo ve grafiklerle sunulmuştur.

Anahtar Kelimeler

Gerilme, Oryantasyon Açısı, Sonlu Farklar Metodu, Şekil Değiştirme, Tabakalı Kompozit Kiriş

BENDING ANALYSIS OF LAMINATED COMPOSITE BEAMS

Öz

In this study; stress and displacement analysis of laminated composite beams were performed using finite difference method. In the analyses, different support conditions and beams under different loading conditions were investigated according to Euler-Bernoulli and Timoshenko beam theories. These examined beams have different lamination scheme and different orientation angles. Laminated composite beams are considered as plane stress problem. When stress and strain analyses were carried out, some assumptions were made for related constitutive links and equilibrium equations. The three-dimensional non-linear deforming expressions were reduced to two-dimensional and linear strain expressions. The central finite difference relations were used to solve these differential equations. For each finite difference node a central finite difference statement was written. These expressions were then rearranged according to the boundary conditions. A software has been developed using the open- source DEV-C++ V 5.8.3 editor for solving the obtained constitutive and equilibrium equations. Numerical applications were performed using this developed program. The sample problems in the literature have been solved and the accuracy of the developed software has been tested. As a result, stress and displacement behaviour of laminated composite beams under loads which has different boundary conditions, lamination scheme and orientation angle were presented. The results were presented in tables and graphs.

Anahtar Kelimeler

Stress, Orientation Angle, Finite Difference Method, Strain, Laminated composite beam

Kaynakça

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