Two approaches have traditionally been used when general shell structures have been analysed. The first approach has been devised by Kirchhoff and Love and later the model has been improved by Koiter. A second class of models is based on the notion of surface introduced by Cosserat. Naghdi has devel
A locking-free finite element method for Naghdi shells
โ Scribed by James H. Bramble; Tong Sun
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 733 KB
- Volume
- 89
- Category
- Article
- ISSN
- 0377-0427
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โฆ Synopsis
In this paper a locking-free method, using mixed finite elements, is introduced to approximate the solution of Naghdi shell problems with small parameter t, the thickness of the shell. The approach of Arnold and Brezzi (1997) is employed with some important changes. Instead of proving the discrete Inf-Sup condition for arbitrary geometric coefficients, which does not seem possible, we prove a weaker stability condition for smooth enough geometrically dependent coefficients, which is sufficient for deducing the optimal error estimate as long as h2/t is uniformly bounded. For extremely small t, we can relax this condition either using a larger bubble space or stabilizing the problem by replacing t 2 by t 2 + h 4. In either case an optimal error estimate still holds. (~) 1997 Elsevier Science B.V. All rights reserved.
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