A hybrid-stress nonuniform Timoshenko beam finite element

Demirhisar, Umut
In this thesis, a hybrid-stress finite element is developed for nonuniform Timoshenko beams. The element stiffness matrix is obtained by assuming a stress field only. Since element boundaries are simply the element nodes, a displacement assumption is not necessary. Geometric and mass stiffness matrices are obtained via equilibrium and kinematics of deformation equations which are derived in the beam arbitrary cross-section. Utilizing this method eliminates the displacement assumption for the geometric and mass stiffness matrices. The element has six degrees of freedom at each node. Axial, flexural and torsional effects are considered. The torsional and distortional warping effects are omitted. Deformations due to shear is also taken into account. Finally, some sample problems are solved with the element and results are compared with the solutions in the literature and commercial finite element programs (i.e. MSC/NASTRAN®).


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Citation Formats
U. Demirhisar, “A hybrid-stress nonuniform Timoshenko beam finite element,” M.S. - Master of Science, Middle East Technical University, 2007.