Minimisation of the mass of aerospace structures has been investigated by researchers and designers for many years. It is an efficient means to reduce the manufacturing costs, fuel consumption and environmental impact. To achieve this objective, high performance composite materials and optimised configurations are utilised in modern aircraft design. Additionally, use of the postbuckling reserve of strength has been considered during the preliminary design stage to obtain more efficient structures. The exact strip analysis and optimum design software VICONOPT has been developed and used in postbuckling analysis. VICONOPT is able to give a good initial evaluation of load versus end shortening when compared with experimental and finite element results. However it provides poor predictions of the stress and strain distributions in the postbuckling range. This is due to its assumptions concerning the longitudinal invariance of stress and the sinusoidal variation of buckling modes in the longitudinal direction. These assumptions are appropriate for initial buckling analysis but they limit the accuracy of subsequent postbuckling analysis. This thesis outlines some developments which improve the existing exact strip postbuckling analysis by improving the accuracy of mode shape prediction and stress and strain distributions. Based on previous research by Von Karman, improved governing equations are derived and solved for general anisotropic plates with different in- plane edge conditions. Implementation of the improved analysis in VICONOPT enhances the accuracy of mode shapes and stress and strain distributions in the postbuckling analysis.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:590317 |
| Date | January 2012 |
| Creators | Che, Bin |
| Publisher | Cardiff University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://orca.cf.ac.uk/56759/ |
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