A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Lateral Stability of Imperfect Discretely Braced Steel Beams
The lateral stability of imperfect discretely braced steel beams is analyzed using Rayleigh-Ritz approximations for the lateral deflection and the angle of twist. Initially, it is assumed that these degrees of freedom can be represented by functions comprising only single harmonics; this is then compared with the more accurate representation of the displacement functions by full Fourier series. It is confirmed by linear eigenvalue analysis that the beam can realistically buckle into two separate classes of modes: a finite number of node-displacing modes, equal to the number of restraints provided, and an infinite number of single harmonic buckling modes, where the restraint nodes remain undeflected. Closed-form analytical relations are derived for the elastic critical moment of the beam, the forces induced in the restraints, and the minimum stiffness required to enforce the first internodal buckling mode. The position of the restraint above or below the shear center is shown to influence the overall buckling behavior of the beam. The analytical results for the critical moment of the beam are validated by the finite-element program LTBeam, whereas the results for the deflected shape of the beam are validated by the numerical continuation software AUTO-07p, with very close agreement between the analytical and the numerical results.
Lateral Stability of Imperfect Discretely Braced Steel Beams
The lateral stability of imperfect discretely braced steel beams is analyzed using Rayleigh-Ritz approximations for the lateral deflection and the angle of twist. Initially, it is assumed that these degrees of freedom can be represented by functions comprising only single harmonics; this is then compared with the more accurate representation of the displacement functions by full Fourier series. It is confirmed by linear eigenvalue analysis that the beam can realistically buckle into two separate classes of modes: a finite number of node-displacing modes, equal to the number of restraints provided, and an infinite number of single harmonic buckling modes, where the restraint nodes remain undeflected. Closed-form analytical relations are derived for the elastic critical moment of the beam, the forces induced in the restraints, and the minimum stiffness required to enforce the first internodal buckling mode. The position of the restraint above or below the shear center is shown to influence the overall buckling behavior of the beam. The analytical results for the critical moment of the beam are validated by the finite-element program LTBeam, whereas the results for the deflected shape of the beam are validated by the numerical continuation software AUTO-07p, with very close agreement between the analytical and the numerical results.
Lateral Stability of Imperfect Discretely Braced Steel Beams
McCann, Finian (author) / Wadee, M. Ahmer (author) / Gardner, Leroy (author)
Journal of Engineering Mechanics ; 139 ; 1341-1349
2012-12-21
92013-01-01 pages
Article (Journal)
Electronic Resource
English
Lateral Stability of Imperfect Discretely Braced Steel Beams
| Online Contents | 2013
Flexural Capacity of Discretely Braced C's and Z's
| British Library Conference Proceedings | 1992
Stability of beams in steel eccentrically braced frames
| Online Contents | 2014
Torsional stiffness requirements for diaphragm bracing of discretely braced I-girders
| Springer Verlag | 2014