PSI - Issue 64

Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2023) 000 – 000 Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 64 (2024) 2254–2262

SMAR 2024 – 7th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures Distress detection in tunnel lining from MLS data A. Di Benedetto a , M. Fiani a, * a Department of Civil Engineering, University of Salerno, Fisciano (SA), Italy Abstract As tunnels age, deterioration of their inner lining worsens, necessitating continuous inspections and evaluations to monitor their condition and implement preventive measures against potential structural damage, thereby avoiding service disruptions. Traditional methods involve visual and manual inspections, leading to temporary closures and resource consumption. The Mobile Laser Scanner (MLS) technique, which is based on LiDAR (Light Detection And Ranging) technology, allows the modeling of the tunnel intrados using a point cloud, without disrupting traffic. Our study introduces a methodology for tunnel intrados analysis utilizing an automated point cloud unrolling algorithm rooted in the RANSAC (RANdom SAmple Consensus) method. Intensity values are examined to identify potential water infiltration, while roughness values evaluate surface integrity and reveal cracks or protruding steel bars. Despite being limited to two types of distress, our research facilitate the identification of tunnel sections necessitating immediate intervention, allowing for the prioritization of high-risk areas, or issuing alerts. © 2024 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 SMAR 2024 Organizers Keywords: LiDAR; MLS; Monitoring; Algorithm; Distress; Infrastructure; Tunnel; Roughness. 1. Introduction In the field of linear infrastructure, the existence of tunnels in geologically intricate and hydrogeologically perilous areas compels managing agencies to increase inspection frequency (Chen et al., 2020; Montero et al., 2015). © 2024 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 SMAR 2024 Organizers

* Corresponding author. Tel.: +39 - 089 964128. E-mail address: m.fiani@unisa.it

2452-3216 © 2024 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 SMAR 2024 Organizers

2452-3216 © 2024 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 SMAR 2024 Organizers 10.1016/j.prostr.2024.09.355