PSI - Issue 84

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ScienceDirect

Procedia Structural Integrity 84 (2026) 1191–1197

© 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: Ground Penetrating Radar; Ultrasonic Tomography; Endoscopies; Ultrasound. Abstract The assessments presented in this report stem from the activities carried out on the Candigliano viaduct, located at km 241+967 of State Road 3 “Flaminia,” during the period January–March 2024. Specifically, the survey involved determining the position and number of prestressing cables using two different ground-penetrating radar scanning methods, performing tomographic analysis of the cables to detect any voids attributable to grout deficiency, and, finally, conducting targeted endoscopic inspections to verify the accuracy of the indications provided by the instrumental surveys. 1. Introduction The technological evolution of instruments intended for carrying out surveys on the structures of civil engineering works allows the application of investigation methodologies that are increasingly accurate and rapid in terms of execution and data output. From this perspective, with progressive miniaturization and the resulting ease of use, the use of ground-penetrating radar (GPR) has become increasingly widespread in recent years as the primary tool for determining reinforcement (both ordinary and prestressed) within reinforced concrete elements. The use of antennas emitting waves at variable frequencies makes it possible to select the most suitable instrument in relation to the III Fabre Conference: Existing Bridges, Viaducts, and Tunnels: Research, Innovation, and Applications Assessment of the effectiveness of survey techniques for reconstructing the layout of prestressing cables and evaluating their state of preservation Luca Ranedda a, *, Calogero Di Vita a , Daniele Insana a , Davide Testa a a Anas S.p.A. – CRSS Diagnostica Strutturale, Via della Stazione di Cesano 311, Rome 00123, Italy

* Corresponding author. Tel.: +39-339-588-5377 E-mail address: l.ranedda@stradeanas.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.2026.06.152