Structural Engineering and Mechanics

  • 제26권1호
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  • Pages.31-42
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  • 2007
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  • 1225-4568(pISSN)
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  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
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DOI QR코드

DOI QR Code

The unsymmetric finite element formulation and variational incorrectness

  • Prathap, G. (CSIR Centre for Mathematical Modelling and Computer Simulation) ;
  • Manju, S. (National Aerospace Laboratories) ;
  • Senthilkumar, V. (CSIR Centre for Mathematical Modelling and Computer Simulation)
  • 투고 : 2005.07.14
  • 심사 : 2006.10.12
  • 발행 : 2007.05.10
⟨ 이전 논문 다음 논문 ⟩

초록

The unsymmetric finite element formulation has been proposed recently to improve predictions from distorted finite elements. Studies have also shown that this special formulation using parametric functions for the test functions and metric functions for the trial functions works surprisingly well because the former satisfy the continuity conditions while the latter ensure that the stress representation during finite element computation can retrieve in a best-fit manner, the actual variation of stress in the metric space. However, a question that remained was whether the unsymmetric formulation was variationally correct. Here we determine that it is not, using the simplest possible element to amplify the principles.

키워드

참고문헌

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피인용 문헌

  1. Use of unsymmetric finite element method in impact analysis of composite laminates vol.47, pp.4, 2011, https://doi.org/10.1016/j.finel.2010.12.016
  2. High-performance unsymmetric 3-node triangular membrane element with drilling DOFs can correctly undertake in-plane moments vol.35, pp.7, 2018, https://doi.org/10.1108/EC-04-2018-0200
  3. Mesh distortion, locking and the use of metric trial functions for displacement type finite elements vol.29, pp.3, 2007, https://doi.org/10.12989/sem.2008.29.3.289
  4. An improved parametric formulation for the variationally correct distortion immune three-noded bar element vol.38, pp.3, 2007, https://doi.org/10.12989/sem.2011.38.3.261
  5. Function space formulation of the 3-noded distorted Timoshenko metric beam element vol.69, pp.6, 2007, https://doi.org/10.12989/sem.2019.69.6.615