PSI - Issue 84

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ScienceDirect

Procedia Structural Integrity 84 (2026) 465–472

© 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; Parabolic tendon; Post–tensioning loss; Shear effect; Solid finite-element; Strand7 Abstract The shear deformation in prestressed concrete girder-bridges under long-age conditions was studied based on the Timoshenko theory. Their shear deformation in terms of second-order effects is usually neglected. In this second article, an additional high fidelity solid finite-element model using the Strand7, assuming geometric nonlinearities and time-dependent post–tensioning losses, was developed to analyze such a topic. A simply supported concrete specimen composed of parabolic tendon, significant slenderness ratio and high-strength concrete was considered. Based on the comparison with static tests performed on such a member, the shear deformation should firmly be assumed for gaining proper accuracies in most structural analyses, even when the concrete girder-bridges have an important length/height ratio. Similar to the first article, the solid finite-element model was then used to determine the parameters of the magnification factor formula. Accordingly, the post–tensioning identification, based on the “static deflected shape” method, requires considering the shear effect. Finally, the compression-softening theory was confirmed for concrete girder-bridges under long-age conditions when cracking is excluded and the second-order shear effects are < 10%. 1. Introduction The prestressing technology was developed for improving the performance of a structure. It was mostly employed for important infrastructures, such as both long-span bridges and viaducts. Thus, the prediction of variation in dynamic III Fabre Conference: Existing Bridges, Viaducts, and Tunnels: Research, Innovation, and Applications Solid finite-element modeling of prestressed beams. Part II: Concrete girder-bridge with a parabolic 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.2026.06.060