Shear resistance of bridge I-girders with diagonal stiffener - design proposal

Ljubinković, Filip (author), Zoubek, Sara (author), Martins, João Pedro (author)

Steel I-girders with diagonal stiffeners offer an effective means of increasing shear resistance in bridge applications by enhancing both elastic buckling and post-buckling resistance. However, no dedicated design rules exist for such configurations in current structural design standards, particularly for carbon steel girders. This study addresses this gap through an extensive numerical investigation of the shear buckling behaviour and ultimate resistance of web panels stiffened along the compression diagonal. A finite element model (FEM), validated against full-scale experiments, supports a broad parametric study covering aspect ratio, web slenderness, stiffener rigidity and geometric imperfections. The numerical results are used to assess existing resistance models, to develop a new expression for the shear buckling coefficient, and to propose several design models for ultimate shear resistance. A reliability assessment confirms compliance with Eurocode target safety levels. The study provides the first validated and comprehensive design framework for carbon-steel I-girders with diagonal stiffeners placed along the compression diagonal, bridging a key gap in current design standards and enabling more efficient and reliable shear design of steel bridge girders.

• Language: English
• Keywords: civil engineering, steel I-girders, diagonal stiffeners, shear buckling coefficient, shear buckling resistance, design model, FEM, reliability
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FGG - Faculty of Civil and Geodetic Engineering
• Publication status: Published
• Publication version: Version of Record
• Publication date: 30.03.2026
• Year: 2026
• Number of pages: 20 str.
• Numbering: art. 110361, Letn. 242
• PID: 20.500.12556/RUL-181467
• UDC: 624.014
• ISSN on article: 0143-974X
• DOI: 10.1016/j.jcsr.2026.110361
• COBISS.SI-ID: 274407939
• Publication date in RUL: 08.04.2026

Record is a part of a journal

• Title: Journal of constructional steel research
• Shortened title: J. Constr. steel res.
• Publisher: Elsevier Science
• ISSN: 0143-974X
• COBISS.SI-ID: 1326341

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.

Secondary language

• Language: Slovenian
• Keywords: gradbeništvo, jekleni I-nosilci, diagonalne ojačitve, koeficient strižnega uklona, strižna nosilnost, računski model, metoda končnih elementov, MKE, zanesljivost

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P2-0158-2018
• Name: Gradbene konstrukcije in gradbena fizika