PSI - Issue 78

Available online at www.sciencedirect.com

ScienceDirect

Procedia Structural Integrity 78 (2026) 1143–1150

© 2025 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 XX ANIDIS Conference organizers Keywords: Bending test; Concrete girder-bridge; Elastic modulus; Post – tensioning; Shear deformation; Small-deflection Abstract Based on the small-deflection theory, simply supported prestressed concrete girder-bridges are shear deformable members because concrete is treated as a shear deformable material. However, when the slenderness of prestressed concrete girder-bridges is significant and elastic shear modulus assumes higher values (high-strength concrete), the shear effect can reasonably be neglected even in presence of finite-stress and shear values. This is generally sufficient for practical purposes in structural engineering. In this contribution, a reference solution and a finite-element model assuming geometric nonlinearities have mainly been implemented to analyze such an issue. According to the comparison with static tests on a concrete beam subjected to different values of post – tensioning, reported in literature, the shear deformation should strongly be considered for a better accuracy in most simulations of structural modeling, and identifying the existing prestressing force through a nondestructive method based on small-deflection measurements. 1. Introduction The prestressing technique, which was developed for the purpose of improving the overall in-service performance of a structure, was widely employed in most important long-span concrete bridges. The prediction of changes in dynamic and static deformations with varying prestressing force in bridges is a crucial problem (Bai-jian et al. 2018; XX ANIDIS Conference Analysis of the shear deformation in simply supported prestressed concrete girder-bridges 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 © 2025 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 XX ANIDIS Conference organizers 10.1016/j.prostr.2025.12.146