The Experts below are selected from a list of 5076 Experts worldwide ranked by ideXlab platform
Aleksandar Prokic - One of the best experts on this subject based on the ideXlab platform.
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new Warping Function for thin walled beams i theory
Journal of Structural Engineering-asce, 1996Co-Authors: Aleksandar ProkicAbstract:Proposing a new Warping Function, the basic equations for thin-walled beams with arbitrary open or closed cross sections are developed. Compared to the classical theory of thin-walled structures, the present approach is more general. The only restriction is that the cross section of the member should remain undeformed in its plane during deformation. The principle of virtual displacements has been used to give the conditions of equilibrium. The finite element method and numerical results are presented in a companion paper.
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new Warping Function for thin walled beams ii finite element method and applications
Journal of Structural Engineering-asce, 1996Co-Authors: Aleksandar ProkicAbstract:In the companion paper, using more general assumptions concerning the Warping, the theory for thin-walled beams with arbitrary open or closed cross section is developed. In this paper, on the basis of the new Warping Function, the finite element model is presented. An updated Lagrangian formulation is used to give a linear and geometric stiffness matrix. To test the accuracy of the theory as well as the performance of the associated finite element, some numerical examples are given.
Friedrich Gruttmann - One of the best experts on this subject based on the ideXlab platform.
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finite element analysis of saint venant torsion problem with exact integration of the elastic plastic constitutive equations
Computer Methods in Applied Mechanics and Engineering, 2001Co-Authors: Werner Wagner, Friedrich GruttmannAbstract:Abstract In this paper torsion of prismatic bars considering elastic–plastic material behaviour is studied. Based on the presented variational formulation associated isoparametric finite elements are developed. The unknown Warping Function is approximated using an isoparametric concept. The elastic–plastic stresses are obtained by an exact integration of the rate equations. Thus the ultimate torque can be calculated in one single load step. This quantity describes the plastic reserve of a bar subjected to torsion. Furthermore, for linear isotropic hardening no local iterations are necessary to compute the stresses at the integration points. The numerical results are in very good agreement with available analytical solutions for simple geometric shapes. The arbitrary shaped domains may be simply or multiple connected.
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Shear correction factors in Timoshenko's beam theory for arbitrary shaped cross-sections
Computational Mechanics, 2001Co-Authors: Friedrich Gruttmann, Werner WagnerAbstract:In this paper shear correction factors for arbitrary shaped beam cross-sections are calculated. Based on the equations of linear elasticity and further assumptions for the stress field the boundary value problem and a variational formulation are developed. The shear stresses are obtained from derivatives of the Warping Function. The developed element formulation can easily be implemented in a standard finite element program. Continuity conditions which occur for multiple connected domains are automatically fulfilled.
Werner Wagner - One of the best experts on this subject based on the ideXlab platform.
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finite element analysis of saint venant torsion problem with exact integration of the elastic plastic constitutive equations
Computer Methods in Applied Mechanics and Engineering, 2001Co-Authors: Werner Wagner, Friedrich GruttmannAbstract:Abstract In this paper torsion of prismatic bars considering elastic–plastic material behaviour is studied. Based on the presented variational formulation associated isoparametric finite elements are developed. The unknown Warping Function is approximated using an isoparametric concept. The elastic–plastic stresses are obtained by an exact integration of the rate equations. Thus the ultimate torque can be calculated in one single load step. This quantity describes the plastic reserve of a bar subjected to torsion. Furthermore, for linear isotropic hardening no local iterations are necessary to compute the stresses at the integration points. The numerical results are in very good agreement with available analytical solutions for simple geometric shapes. The arbitrary shaped domains may be simply or multiple connected.
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Shear correction factors in Timoshenko's beam theory for arbitrary shaped cross-sections
Computational Mechanics, 2001Co-Authors: Friedrich Gruttmann, Werner WagnerAbstract:In this paper shear correction factors for arbitrary shaped beam cross-sections are calculated. Based on the equations of linear elasticity and further assumptions for the stress field the boundary value problem and a variational formulation are developed. The shear stresses are obtained from derivatives of the Warping Function. The developed element formulation can easily be implemented in a standard finite element program. Continuity conditions which occur for multiple connected domains are automatically fulfilled.
Chen Weiqiu - One of the best experts on this subject based on the ideXlab platform.
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saint venant torsion of orthotropic bars with inhomogeneous rectangular cross section
Composite Structures, 2010Co-Authors: Xu Rongqiao, He Jiansheng, Chen WeiqiuAbstract:This work presents an exact solution of the Saint-Venant torsion of a straight bar with an orthotropic and inhomogeneous rectangular cross section whose material properties obey the exponential law in one direction. An approximate solution is also obtained for the material properties being arbitrarily distributed in one direction by using a layerwise model, in which the inhomogeneous rectangle is simulated by a composite rectangle composed of multiple rigidly connected homogeneous rectangular regions. The Warping Function, stresses and torsional rigidity are analytically expressed in terms of Fourier series for both solutions, in which the hyperbolic Functions are not directly employed to avoid numerical difficulties. Some numerical examples are finally presented to verify the proposed method and the parametrical study is also performed.
M.m. Monfared - One of the best experts on this subject based on the ideXlab platform.
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Analysis of cracked bars with rectangular cross-section and isotropic coating layer under torsion
International Journal of Mechanical Sciences, 2017Co-Authors: Alireza Hassani, M.m. MonfaredAbstract:Abstract The solution to problem of a Volterra-type screw dislocation in a rectangular cross section bar with an isotropic coating is first achieved by means of a finite Fourier cosine transform. The bar is under axial torque which is governed by Saint-Venant torsion theory. The series solution is then derived for Warping Function and stress fields in the rectangular cross section with an isotropic coating. The dislocation solution is employed to derive a set of Cauchy singular integral equations for the analysis of smooth cracks. The solution of these equations is used to determine the torsional rigidity of bar and the stress intensity factors for the crack tips. Finally, several examples are presented to show the accuracy and efficiency of the dislocation technique in Saint-Venant torsion problems.
