Extended virtual element method for the torsion problem of cracked prismatic beams
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In this paper, we investigate the capability of the recently proposed extended virtual element method (X-VEM) to efficiently and accurately solve the problem of a cracked prismatic beam under pure torsion, mathematically described by the Poisson equation in terms of a scalar stress function. This problem is representative of a wide class of elliptic problems for which classic finite element approximations tend to converge poorly, due to the presence of singularities. The X-VEM is a stabilized Galerkin formulation on arbitrary polygonal meshes derived from the virtual element method (VEM) by augmenting the standard virtual element space with an additional contribution that consists of the product of virtual nodal basis functions with a suitable enrichment function. In addition, an extended projector that maps functions lying in the extended virtual element space onto linear polynomials and the enrichment function is employed. Convergence of the method on both quadrilateral and polygonal meshes for the cracked beam torsion problem is studied by means of numerical experiments. The computed results affirm the sound accuracy of the method and demonstrate a significantly improved convergence rate, both in terms of energy and stress intensity factor, when compared to standard finite element method and VEM.
KeywordsVirtual element method Extended virtual element method Partition of unity method Cracked beam torsion problem Singularities Polygonal meshes
The Authors are grateful to Prof. N. Sukumar and Dr. G. Manzini for their valuable contributions to the developments contained in this paper.
This study was funded by Ministero dell’Istruzione, dell’ Università e della Ricerca, PRIN: Progetti di Ricerca di Rilevante Interesse Nazionale (Grant No. 2015LYYXA8).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- 2.Sih G, Paris P, Erdogan F (1962) Crack-tip, stress-intensity factors for plane extension and plate bending problems. J Appl Mech 29(2):306–312Google Scholar
- 9.Sukumar N, Dolbow JE, Moës N (2015) Extended finite element method in computational fracture mechanics: a retrospective examination. Int J Fract 196(1):189–206Google Scholar
- 23.Barré de Saint-Venant A (1856) De la torsion des prismes avec des considérations sur leurs flexion ainsi que sur l’équilibre des solides élastiques en général et des formules pratiques pour le calcul de leur résistance à divers efforts s’exerçant simultanément, ImprimerieGoogle Scholar
- 37.Bathe K (1982) Finite element procedures in engineering analysis. Prentice-Hall, Englewood CliffsGoogle Scholar