PSI - Issue 84

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ScienceDirect

Procedia Structural Integrity 84 (2026) 457–464

© 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the Conference Keywords: Concrete girder-bridge; Post–tensioning; Shear effect; Solid finite-element; Straight tendon; Strand7 Abstract Prestressed concrete girder-bridges are shear deformable beams because concrete is a shear deformable material. Their shear deformation in terms of second-order effects is usually neglected since the slenderness of concrete girder-bridges is generally significant. This is commonly the practice in applications of bridge engineering. In this article, a high-fidelity solid finite-element model using the Strand7 program, and assuming geometric nonlinearities, was accomplished to study such an issue. Comparisons with static tests executed on a simply supported concrete specimen composed of straight tendon, significant slenderness ratio, high strength concrete, and subjected to different post–tensioning, reported in literature, were elaborated. Subsequently, with the aim to identify the effective post–tensioning forces, the solid finite-element model was adopted to compute the parameters of the magnification factor formula of the second-order shear effects. Accordingly, the shear deformation in prestressed concrete girder bridges should highly be considered for obtaining better accuracies, in terms of results, in most evaluation techniques. Yet, this work was a preparatory contribution with the goal to simulate the “static deflected shape” method for predicting prestressing force in a multi-span concrete girder-bridge based on small-deflection measurements. Moreover, in the second article of this work, a concrete specimen with parabolic tendon, and subjected to time-dependent post–tensioning losses, was instead taken into consideration. III Fabre Conference: Existing Bridges, Viaducts, and Tunnels: Research, Innovation, and Applications Solid finite-element modeling of prestressed beams. Part I: Concrete girder-bridge with a straight tendon Marco Bonopera a, *, Gianfranco De Matteis a a Department of Architecture and Industrial Design, University of Campania “Luigi Vanvitelli”, Via San Lorenzo ad Septimum, Aversa (CE) 81031, Italy

* Corresponding author. Tel.: +39-081-5010700 ; fax: +39-081-5010704 . E-mail address: marco.bonopera@unicampania.it

2452-3216 © 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the Conference 10.1016/j.prostr.2026.06.059