Formulations for locking treatment in anisotropic large deformation elasto-plastic thin structures

• Type: Article in International Conference Proceedings Book
• Date: 2005

Authors

fontes valente, ra (Author) Other; parente, mpl (Author) Other; natal jorge, rm (Author) FEUP; cesar de sa, jma (Author) Other; gracio, jj (Author) Other

Conference proceedings International

Title: Computational Plasticity: Fundamentals and Applications - Proceedings of the 8th International Conference on Computational Plasticity, COMPLAS VIII

Pages: 351-354

8th International Conference on Computational Plasticity: Fundamentals and Applications, COMPLAS VIII

Barcelona, 5 September 2005 through 7 September 2005

Indexing

ISI Web of Knowledge

Scopus - 0 Citations

Other information

Authenticus ID: P-008-2KC

Abstract (EN): In the present work the authors show results obtained with the implementation of an Enhanced Assumed Transverse Strain methodology for thin shells, taking into account anisotropic material nonlinearities, in problems involving large deformations, displacements and rotations. Transverse shear and membrane locking patterns are removed from the original formulation, solely based on the displacement field. The resultant bilinear (4 nodes) shell finite element, fully integrated and with 20 nodal degrees-of-freedom, does not rely on any other mixed formulation. The enhanced strain field is properly designed to enlarge the null transverse shear strain subspace coming from the classical degenerated formulation. At the same time, a minimum number of enhanced variables is involved in the core formulation. A shell element can then be attained with the same predictability as one based on a reduced integrated formulation, but not incorporating spurious energetic modes. Non-linear effects are treated in a local reference frame, only affected by the rigid-body part of the total deformation. Additive and multiplicative update procedures for the finite rotation degrees-of-freedom are implemented, in order to correctly reproduce midpoint configurations along the incremental deformation path. Stress and strain tensors are additively updated in the local frame, together with the enhancing strain field. The final enhanced strain tensor come from a straightforward implementation of nonlinear geometric and material relations. The accuracy of the implemented formulation can be shown in a set of isotropic and anisotropic elasto-plastic problems, in smooth and non-smooth shell structures. Obtained results with the present formulation are in close agreement with either simulation and experimental data.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 4