Influence of Girder Flaring on Load Effect in Girders of Composite Steel Bridges

A flared or splayed girder bridge is a structure made up of a concrete slab on girders with linearly varying spacing along the length. For such an irregular bridge, the girder distribution factors in the AASHTO LRFD Bridge Design Specifications are not applicable. In lieu of using a refined method o...

Full description

Saved in:
Bibliographic Details
Main Authors: Faress Hraib, Sami W. Tabsh
Format: Article
Language:English
Published: MDPI AG 2025-04-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/15/9/4674
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850031999646957568
author Faress Hraib
Sami W. Tabsh
author_facet Faress Hraib
Sami W. Tabsh
author_sort Faress Hraib
collection DOAJ
description A flared or splayed girder bridge is a structure made up of a concrete slab on girders with linearly varying spacing along the length. For such an irregular bridge, the girder distribution factors in the AASHTO LRFD Bridge Design Specifications are not applicable. In lieu of using a refined method of analysis, the study at hand proposes a simple approach for computing the dead and live load effect in the girders. To do so, fifteen composite steel girder bridges are analyzed by the finite element method to determine the influence of the girder flaring angle, girder spacing, number of girders, deck slab thickness, span length, girder stiffness, and presence of cross-bracing on the load distribution within the bridge. This study showed that the tributary width concept is a reliable approach for determining the dead load effect on the splayed girders, especially for the case of shored construction. The girder distribution factors for flexure in the AASHTO specifications can be reasonably utilized for such irregular bridges if the girder spacing at the location of each truck axle is considered, leading to a maximum of 14% difference on the conservative side between the AASHTO approach and the finite element analysis. On the other hand, the lever rule can provide a good estimate of the live load distribution among the splayed girders when subjected to shear, as the maximum safe deviation from the finite element outcome in this situation is less than 10%.
format Article
id doaj-art-88a1e7c386144aa2acc7c03aabe6ed5a
institution DOAJ
issn 2076-3417
language English
publishDate 2025-04-01
publisher MDPI AG
record_format Article
series Applied Sciences
spelling doaj-art-88a1e7c386144aa2acc7c03aabe6ed5a2025-08-20T02:58:47ZengMDPI AGApplied Sciences2076-34172025-04-01159467410.3390/app15094674Influence of Girder Flaring on Load Effect in Girders of Composite Steel BridgesFaress Hraib0Sami W. Tabsh1ABNA, 4140 Lindell Boulevard, St. Louis, MO 63108, USADepartment of Civil Engineering, College of Engineering, American University of Sharjah, Sharjah 26666, United Arab EmiratesA flared or splayed girder bridge is a structure made up of a concrete slab on girders with linearly varying spacing along the length. For such an irregular bridge, the girder distribution factors in the AASHTO LRFD Bridge Design Specifications are not applicable. In lieu of using a refined method of analysis, the study at hand proposes a simple approach for computing the dead and live load effect in the girders. To do so, fifteen composite steel girder bridges are analyzed by the finite element method to determine the influence of the girder flaring angle, girder spacing, number of girders, deck slab thickness, span length, girder stiffness, and presence of cross-bracing on the load distribution within the bridge. This study showed that the tributary width concept is a reliable approach for determining the dead load effect on the splayed girders, especially for the case of shored construction. The girder distribution factors for flexure in the AASHTO specifications can be reasonably utilized for such irregular bridges if the girder spacing at the location of each truck axle is considered, leading to a maximum of 14% difference on the conservative side between the AASHTO approach and the finite element analysis. On the other hand, the lever rule can provide a good estimate of the live load distribution among the splayed girders when subjected to shear, as the maximum safe deviation from the finite element outcome in this situation is less than 10%.https://www.mdpi.com/2076-3417/15/9/4674finite element methodflared girdersgravity loadshighway bridgescomposite steel girdersgirder distribution factor
spellingShingle Faress Hraib
Sami W. Tabsh
Influence of Girder Flaring on Load Effect in Girders of Composite Steel Bridges
Applied Sciences
finite element method
flared girders
gravity loads
highway bridges
composite steel girders
girder distribution factor
title Influence of Girder Flaring on Load Effect in Girders of Composite Steel Bridges
title_full Influence of Girder Flaring on Load Effect in Girders of Composite Steel Bridges
title_fullStr Influence of Girder Flaring on Load Effect in Girders of Composite Steel Bridges
title_full_unstemmed Influence of Girder Flaring on Load Effect in Girders of Composite Steel Bridges
title_short Influence of Girder Flaring on Load Effect in Girders of Composite Steel Bridges
title_sort influence of girder flaring on load effect in girders of composite steel bridges
topic finite element method
flared girders
gravity loads
highway bridges
composite steel girders
girder distribution factor
url https://www.mdpi.com/2076-3417/15/9/4674
work_keys_str_mv AT faresshraib influenceofgirderflaringonloadeffectingirdersofcompositesteelbridges
AT samiwtabsh influenceofgirderflaringonloadeffectingirdersofcompositesteelbridges