Geometrically nonlinear stiffness of web-core sandwich plate
No Thumbnail Available
URL
Journal Title
Journal ISSN
Volume Title
School of Engineering |
Master's thesis
Checking the digitized thesis and permission for publishing
Instructions for the author
Instructions for the author
Authors
Date
2013
Department
Major/Subject
Laivanrakennusoppi
Mcode
Kul-24
Degree programme
Language
en
Pages
53 s. + liitt. 7
Series
Abstract
Stiffness of the unit cell of a web-core sandwich plate is studied in this thesis. The effect of geometrical imperfections is assessed. The unit cell is presented by the stiffness matrices based on the equivalent single layer theory. The geometrically nonlinear behaviour of stiffness components are obtained numerically by exposing the unit cell to one particular loading condition in each analysis. The first buckling Eigen-mode of the unit cell in web-plate direction is considered as the initial imperfection shape since it resembles to production imperfections. Results are in good agreement with theoretical values with an error less than 5% before the imperfections effect become dominant after that the nonlinear behaviour of stiffness coefficients starts to deviate from the theoretical values. The study has shown that geometrical imperfections significantly affect the plate stiffness coefficients. The method is potentially applicable to large complex structures in order to achieve the response of such structures with a realistic model due to consideration of the effect of geometrical imperfections. This new method can be determined as the first step for coupling the local and global buckling of structures via a numerical approach. Since the presented approach uses the equivalent single layer theory, the time and cost efficiency of the method is high.Description
Supervisor
Romanoff, JaniThesis advisor
Jelovica, JasminKeywords
nonlinear finite element analysis, local buckling, equivalent single layer theory, stiffness matrices, geometrical imperfections, web-core sandwich plate