Influence of secondary torsion on curved steel girder bridges with box and I-girder cross-sections

Risultato della ricerca: Articlepeer review

Abstract

Steel curved girder bridges are largely used today in motorways and railways. They are often composed of thin-walled cross-sections, entirely made of steel or with an upper concrete slab. The deck may have I-girders or box cross-sections: in any casecurved girders are subjected to twisting moment, associated with bending, even fordead loads. Moreover, in thin-walled sections the influence of non-uniform torsion becomes sizable with respect to Saint Venant torsion, modifying the state of tangentialstresses in the section and introducing axial stresses due to warping being prevented. Open sections of I-girder bridges are especially subject to these phenomena andwarping can be significant not only for curved bridges but also for eccentrically applied traffic loads in straight ones. In this paper a method for the evaluation of the effects ofnon-uniform torsion, based on an energetic approach, is proposed; the method is simple and fast, with a reduced computational burden with respect to finite elements. The solution of curved girder bridges is performed by the Hamiltonian Structural Analysis method, which is implemented for straight and curved girders with thin-walled cross-sections. A parametric analysis is proposed for single and multi-span bridges, with variation in type of loads applied, cross-section parameters, geometric curvatureof bridge deck and stiffness ratios of the cross-section. The parametric study ispresented through dimensionless diagrams of internal forces for the evaluation of theglobal behaviour of curved girder bridges together with indications on the stress state of the cross-section. The interpretation of the results of the analyses performed can be useful to designers for the conceptual design stages and for optimization of thegeometric and mechanical parameters of I-girder and box girder cross-sections.
Lingua originaleEnglish
Numero di pagine15
RivistaKSCE Journal of Civil Engineering
Volume19
Stato di pubblicazionePublished - 2014

Fingerprint Entra nei temi di ricerca di 'Influence of secondary torsion on curved steel girder bridges with box and I-girder cross-sections'. Insieme formano una fingerprint unica.

Cita questo