Analysis tools for size and shape design of laminated composite shells

Progressive failure analysis of composite shells Olcay, Yasemin; Darendeliler, Haluk; Department of Mechanical Engineering (2012) The objective of this thesis is to investigate the progressive failure behavior of laminated fiber reinforced composite shell structures under different loading conditions. The laminates are assumed to be orthotropic and the first order shear deformation theory is applied. Three-node layered flat-shell elements are used in the analysis. To verify the numerical results obtained, experimental and analytical results found in literature are compared with the outputs of the study, and the comparison is found to ...
Failure analysis of thick composites Erdem, Melek Esra; Parnas, Kemal Levend; Department of Mechanical Engineering (2013) A three-dimensional finite element model is constructed to predict the failure of a hybrid and thick laminate containing bolted joints. The results of the simulation are compared with test results. The simulation comprises two main challenging steps. Firstly, for a realistic model, a 3D model is established with geometric nonlinearities and contact is takeninto account. The laminated composite model is constructed by 3D layered elements. The effect of different number of elements through the thickness is in...
Experimental and numerical investigation of damage process in composite laminates under low-velocity impact Topaç, Ömer Tanay; Çöker, Demirkan; Gürses, Ercan; Department of Aerospace Engineering (2016) Damage sensitivity of composites under out-of-plane dynamic loading, and its limited detectability on a structure has long remained a prominent problem in industry. In this study, simulations are compared with the real-time damage formation scheme, with the aim of increasing confidence in failure predictions. Drop-weight impact experiments are carried out on a [0/90]_s CFRP beam laminate. Initiation and progression of damage, consisting of matrix cracks and delamination, are visualized via ultra-high-speed ...
Numerical investigation of stiffened composite panel into buckling and post buckling under combined loading Akay, Erkan; Yaman, Yavuz; Department of Aerospace Engineering (2015) This thesis presents the investigation of buckling and post buckling behaviour of stiffened thin walled laminated composite aerospace structures subjected to combined in-plane axial and shear loadings. Due to the fact that the state of stress developing especially in the post-buckling stage is quite complicated under the combined loading, the necessary computational model is usually based on Finite Element Modelling (FEM). In this study, after verifying the FEM methodology and completing the sensitivity stu...
Fatigue and static behavior of curved composite laminates Taşdemir, Burcu; Çöker, Demirkan; Department of Aerospace Engineering (2018) By virtue of the fact that curved composite laminates which are utilized as load carrying subcomponents in aircraft and wind turbine structures are subjected to cyclic loading during their operating time, it is crucial to understand fatigue failure mechanisms at least as much as static failure mechanisms. With the intention of understanding fatigue failure mechanisms and thus improving fatigue life of structures, these curved laminates are investigated experimentally under static and fatigue loadings. The f...

Citation Formats

F. Cıbır, “Analysis tools for size and shape design of laminated composite shells,” Ph.D. - Doctoral Program, Middle East Technical University, 2001.