Nonlinear Finite Element Analysis of Bending of Straight Beams Using hp-Spectral Approximations

Subject Areas : Engineering

R Ranjan ¹

1 - SiViRT Center, University of Texas, San Antonio Department of Mechanical Engineering San Antonio

Received: 2011-01-04 Accepted : 2011-04-30 Published : 2011-03-30

Keywords: Timoshenko Beam Theory, spectral/hp method, Euler-Bernoulli beam theory, Nodal expansions, Displacement and mixed finite element models,

Abstract :

Displacement finite element models of various beam theories have been developed using traditional finite element interpolations (i.e., Hermite cubic or equi-spaced Lagrange functions). Various finite element models of beams differ from each other in the choice of the interpolation functions used for the transverse deflection w, total rotation φ and/or shear strain γxz, or in the integral form used (e.g., weak form or least-squares) to develop the finite element model. The present study is concerned with the development of alternative beam finite elements using hp-spectral nodal expansions to eliminate shear and membrane locking. Both linear and non-linear analysis are carried out using both displacement and mixed finite element models of the beam theories studied. Results obtained are compared with both analytical (series) solutions and non-linear finite element solutions from literature, and excellent agreement is found for all cases.

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