FAILURE BEHAVIOUR OF TWO SERIAL BOLTED CROSS-PLY LAMINATED COMPOSITE PLATES

Bu çalışmada, birbirine seri çift cıvata bağlantılı tabakalı kompozit plakaların hasar davranışı deneysel olarak incelenmiştir. Tabakalı kompozit levhaların üretiminde, takviye elemanı olarak cam lifleri ve matris malzemesi olarak epoksi kullanılmıştır. Tabaka dizilişi olarak, çapraz [02Ëš/902Ëš]s takviyeli simetrik oryantasyon seçilmiştir. Levhaların üretiminden sonra, belirlenen çeşitli boyutsal değişkenlere göre deney numuneleri hazırlanmıştır. Bilgisayara bağlı çekme cihazı kullanılarak yapılan deneyler ile bağlantılardaki maksimum hasar yükleri elde edilmiştir. Bu sonuçlar kullanılarak, yatak mukavemetleri hesaplanmış ve numunelerin incelenmesi ile hasar tipleri tespit edilmiştir. Deneysel çalışma sonuçlarına göre, seri çift cıvata bağlantılı kompozit numunelerde incelenen geometrik değişkenlerin, hasar davranışını önemli şekilde etkilediği anlaşılmıştır. Bir başka şekilde ifade etmek gerekirse, maksimum hasar yükleri ile yatak mukavemetlerinin değerlerinin ve hasar tiplerinin oluşumunun geometrik parametrelere bağlı olarak değiştiği tespit edilmiştir In this study, failure bahaviour of two serial bolted laminated composite plates was investigated experimentally. During the production of laminated composite plates, glass fibers and epoxy were used as reinforcement and matris materials, respectively. The orientation of laminas were preferred as cross-ply and symmetric, [02Ëš/902Ëš]s. After the production of plates, the specimens were pepared according to various dimensional parameters. The maximum failure loads were obtained from experiments via tensile test machine connected a computer. The bearing strengths were calculated using experimental failure loads and failure types were determined from observations of tested specimens. It is understand that, according to experimental study results, failure behavior of two serial bolted kompozit specimens were effected from geometrical parameters strictly. On the other hand, the magnitudes of maximum failure loads, bearing strengths and the creation of failure types were changed related to geometrical parameter

A non-linear elastic-plastic stress analysis in a ductile double-lap joint

In this study, an elastic-plastic stress analysis was proposed in order to obtain shear stress distribution in a double-lap joint, analytically. The solution was carried out using incremental theory. The obtained shear stress was then used for determining the peel stress in the adhesive. The elastic peel stress distribution in the adhesive was determined using Newton-Raphson method. In this study, FM73 (Cytec Industries Inc., New Jersey, USA) ductile adhesive was selected as it represents plastic hardening. The analytical results were compared with the finite element solution. For that, ANSYS 10 Software (Figes Engineering A.S., Turkey) was used so as to compare with the analytical results. A good agreement was obtained between the two methods