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This paper presents ARCHITA: an innovative multidimensional mobile mapping system for the survey and the diagnostic of tunnels and infrastructures. The system gives the outputs of geometry and structures conditions in an integrated environment. The paper provides a brief description of the system and the successful application to support the decision-makers and the designers. Moreover, the outputs of the system are presented throughout the paper for different tunnels.

This paper presents the implementation, validation and application of the PM4Sand model (version 3) formulated by Boulanger and Ziotopoulou (2015) in the PLAXIS finite element code. The model can be used for modelling geotechnical earthquake engineering applications, especially in the case liquefaction is likely to occur. The PM4Sand model represents an improvement of the elasto-plastic, stress ratio controlled, bounding surface plasticity model for sands formulated by Dafalias and Manzari (2004). The two-dimensional version has been implemented in PLAXIS and compared to the original implementation by Boulanger and Ziotopoulou (2015). The original implementation has been used in explicit finite difference simulations which can be sensitive to the size of the returned stress increment, based on the chosen time step size and loading rate. Therefore, the user needs to evaluate the sensitivity of the solution with respect to the chosen time step sizes. On the contrary, in the finite element method used here, the default time step together with the sub-stepping used at the constitutive model level, provide a robust solution independent of the size of the returned stress increment.

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In the countries bordered by the sea, it’s common to have an infrastructure in proximity or on the coastlines. The strategic value of transportation systems along the sea is still fundamental for commercial, emergency and touristic purposes. The sea level and the action of the sea waves are relevant issues for the safety and protection of the infrastructure. The Genova-Ventimiglia railway runs along the coast of the Liguria region of Italy. The meteoric events and the sea storms between November 2019 and June 2020 caused different issues along a stretch of the line. The paper presents the study, the planning and the design of the mitigation measures. An investigation campaign involved both the existing structures and the geological context. The structures on the sea are investigated with GPRs analyses and specific tests performed by rock-climbers during the night disruptions of the line. The geotechnical-geomechanical tests revealed a scenario with the western Liguria Flysch in different facies. ETS Srl has also implemented and deployed a marine Unmanned Surface Vehicle (USV) for the bathymetric survey. The processed data are integrated with the topographic survey to obtain a 3D reconstruction of both the above-sea and undersea surface. The aforementioned data are used for the study, the characterization of the materials and the design of the solution to reinforce the existing structures and mitigate the erosion effect near the line.