Abstract
Bridge prestressed concrete girders are vulnerable to sudden rupture of prestressing strands caused by accidental collisions with over-height trucks. These incidents often result in the asymmetric loss of prestressing strands and concrete sections, generating a biaxial bending moment caused by the combined effects of lateral bending and existing service loads. The induced lateral bending moment reduces the flexural resistance of prestressed concrete (PC) girders. However, the current AASHTO LRFD (load and resistance factor design) provisions for flexural resistance in PC members do not explicitly address the complexities introduced by biaxial bending, leaving the extent of strength reduction uncertain. This paper presents a series of 3-D nonlinear finite element (FE) models developed using LS-DYNA software. Four models were validated against full-scale experimental data. Force-deflection relationships were established, and the FE results were compared with predictions based on AASHTO LRFD provisions. This study concludes that lateral bending moments resulting from asymmetric losses of prestressing strands and concrete section reductions can reduce flexural resistance. The findings reveal that the AASHTO LRFD flexural resistance overestimates the residual flexural capacity of girders affected by biaxial bending by an average margin of 15%. To address this, an accidental lateral eccentricity reduction factor ΨIM of 0.85 is proposed for quickly incorporating the effects of biaxial bending in scenarios similar to those modeled in this study. The proposed factor is based on idealized FE simulations and is not intended for universal application to all impact damage cases. For real-world incidents, a case-specific assessment using refined analysis and diagnostics is recommended.
Recommended Citation
H. AbdelMalek et al., "Biaxial Bending Response of Prestressed Concrete Girders Subjected to Accidental Asymmetric Prestressing Strand Loss," Transportation Research Record, SAGE Publications, Jan 2026.
The definitive version is available at https://doi.org/10.1177/03611981251407916
Department(s)
Civil, Architectural and Environmental Engineering
Publication Status
Available Access
Keywords and Phrases
biaxial bending moment; bridge prestressed concrete girder; finite element; flexural strength; LS-DYNA; vehicle collision
International Standard Serial Number (ISSN)
2169-4052; 0361-1981
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2026 SAGE Publications, All rights reserved.
Publication Date
01 Jan 2026
