Title
Locking-free finite element method for a bending moment formulation of Timoshenko beams
Abstract
In this paper we study a finite element formulation for Timoshenko beams. It is known that standard finite elements applied to this model lead to wrong results when the thickness of the beam is small. Here, we consider a mixed formulation in terms of the transverse displacement, rotation, shear stress and bending moment. By using the classical Babuska-Brezzi theory, it is proved that the resulting variational formulation is well posed. We discretize it by continuous piecewise linear finite elements for the shear stress and bending moment, and discontinuous piecewise constant finite elements for the displacement and rotation. We prove an optimal (linear) order of convergence in terms of the mesh size for the natural norms and a double order (quadratic) in L^2-norms for the shear stress and the bending moment. These estimates involve constants and norms of the solution that are proved to be bounded independently of the beam thickness, which ensures the locking-free character of the method. Numerical tests are reported in order to support our theoretical results.
Year
DOI
Venue
2014
10.1016/j.camwa.2014.05.011
Computers & Mathematics with Applications
Keywords
Field
DocType
mixed finite elements,error analysis,locking-free,timoshenko beams,bending moment formulation
Bending moment,Timoshenko beam theory,Pure bending,Mathematical analysis,Bending,Finite element method,Bending stiffness,Beam (structure),Shear and moment diagram,Mathematics
Journal
Volume
Issue
ISSN
68
3
0898-1221
Citations 
PageRank 
References 
1
0.36
7
Authors
3
Name
Order
Citations
PageRank
Felipe Lepe121.41
David Mora2348.92
R. Rodríguez37219.18