Contributions to the anisotropic elasto-plastic analysis of shells

Shells are probably the most widely used structural component in engineering and also in nature due to their high efficiency and excellent performance when properly designed. On the other hand, they can be very sensitive to changes in geometries, thicknesses, applied loads and boundary conditions. Hence much research effort has been devoted to the reliable and efficient analysis of shells. This work contributes to the anisotropic elasto-plastic analysis of shells by addressing key issues in developing shell elements for finite element analysis and an elasto-plasticity model considering anisotropy and its evolution. First we develop a shell element that models the three-dimensional (3D) effects of surface tractions. The element is the widely used MITC4 shell element enriched by the use of a fully 3D stress-strain description, appropriate through-the-thickness displacements to model surface tractions, and pressure degrees of freedom for incompressible analyses. The element formulation avoids instabilities and ill-conditioning. We also develop a triangular 6-node shell element that represents an important improvement over a recently published element. The element is spatially isotropic, passes the membrane and bending patch tests, contains no spurious zero energy mode, and is formulated without an artificial constant. In particular, the improved element does not show the instability sometimes observed with the earlier published element.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Kim, Do-Nyun

Advisor dc:contributor.advisor

• Klaus-Jürgen Bathe.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/49760

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/49760