PSI - Issue 84

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ScienceDirect

Procedia Structural Integrity 84 (2026) 191–198

III Fabre Conference: Existing Bridges, Viaducts, and Tunnels: Research, Innovation, and Applications InSAR and FEM analysis of the interaction between a highway

bridge and a slow-moving landslide Alice Vitaletti a *, Erica Cernuto b , Diana Salciarini b

a Department of Civil and Industrial Engineering, University of Pisa, Largo L. Lazzarino 1, 56122 Pisa, Italy b Department of Civil and Environmental Engineering, University of Perugia, Via G. Duranti 93, 06125 Perugia, Italy

© 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 Abstract The Italian territory, due to its complex geological and geomorphological structure, is highly susceptible to landslides. Among natural hazards, landslides pose a major threat to infrastructure, and the increasing occurrence of collapses, structural damage, and service disruptions highlights the importance of better understanding their interaction. Therefore, monitoring slope instability has become essential for infrastructure managers, especially along highway networks exposed to recurrent landslide activity. This study investigates the interaction between a slow-moving landslide and a highway bridge in the Liguria region, based on a real scenario documented in the Inventory of Landslide Phenomena in Italy (IFFI). The proposed approach combines Interferometric Synthetic Aperture Radar (InSAR) data from Copernicus European Ground Motion Service (EGMS) with Finite Element Method (FEM) numerical modelling. Post-processed InSAR data enabled the estimation of actual transverse and vertical displacement components through spatial-temporal interpolation and projection in a landslide-fixed local reference system, supporting the assessment of slope kinematics. The 3D FEM model, aimed at simulating landslide behaviour under hydro-mechanical loads and evaluating the bridge response, revealed significant deformations at the base of piers within the landslide-affected volume, due to horizontal forces on the foundations. The numerical simulation reproduced deformation patterns consistent with satellite-derived displacements, particularly in the downstream portion of the slope. The qualitative consistency between InSAR and FEM results confirmed the effectiveness of the combined approach in detecting susceptible areas and interpreting satellite data to assess bridge performance in landslide-prone contexts.

* Corresponding author. E-mail address: alice.vitaletti@phd.unipi.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.2026.06.026