Numerical investigation of stiffened composite panel into buckling and post buckling under combined loading

Akay, Erkan
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 studies, the buckling and post buckling phenomenon are examined in order to see the effects of shear loading beside the axial compressive loading on a stiffened composite panel via linear and nonlinear analyses. The results show that under combined in-plane loading of a stiffened panel, additional shear loading beside the axial loading has an influence on the axially critical buckling load capability of the structure depending on the characteristic of the structure like ply orientation.


Behavior of steel-concrete partially composite beams with channel type shear connectors
Baran, Eray; Topkaya, Cem (2014-06-01)
This paper summarizes the findings of an experimental study investigating the flexural behavior of partially composite beams incorporating channel type shear connectors. Results from monotonic load testing of four full-scale steel-concrete composite beams and a steel beam are presented. The main effort focused on identifying the variation of strength and stiffness properties of beams with various degrees of partial composite action. Behavior of channel shear connectors in the composite beam specimens is rel...
Numerical analysis of ablation process on a two dimensional external surface
Aykan, Fatma Serap; Dursunkaya, Zafer (2008-01-01)
The thermal response analysis of an ablative material on a two dimensional external surface is performed. The method considers the whole domain as one continuous computational domain, eliminating the necessity to check the starting and ending positions of the decomposition zone. The current study solves the decomposition of the material at high temperatures by using the nth order Arrhenius equation but excludes the removal of char from the surface due to mechanical erosion or phase change and considers that...
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 ...
Development of computational software for analysis of curved girders under construction loads
Topkaya, Cem (Elsevier BV, 2003-09-01)
The analysis of horizontally curved, trapezoidal steel girders presents a variety of computational challenges. During the erection and construction stages before a concrete deck is available to form a closed section, these girders are weak in torsion and susceptible to warping. Considering the design of an entire bridge system, current design approaches favor the use of a grid analysis methodology. While the use of a grid analysis procedure offers the advantage of computational efficiency, it is unable to c...
Numerical simulation of dynamic shear wall tests: A benchmark study
Kazaz, I; Yakut, Ahmet; Gulkan, P (2006-03-01)
This article presents the numerical simulation of a 1/3-scale, 5-story reinforced concrete load bearing structural wall model subjected to seismic excitations in the context of IAEA benchmark shaking table experiment conducted in laboratories of CEA in Saclay, France. A series of non-linear time history analyses were performed to simulate the damage experienced and response quantities measured for the specimen tested on a shaking table. The mock-up was subjected to a series of artificial and natural earthqu...
Citation Formats
E. Akay, “Numerical investigation of stiffened composite panel into buckling and post buckling under combined loading,” M.S. - Master of Science, Middle East Technical University, 2015.