PSI - Issue 62

Erika Garusi et al. / Procedia Structural Integrity 62 (2024) 233–240 E. Garusi et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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• The technical control of the efficiency of roads and their appurtenances. • The posting and maintenance of prescribed signs.

The concessionaries are usually private companies to which the State grants a concession for the construction or maintenance of a highway by collecting tolls. In accordance with above mentioned art. 14 of the New Road Code ND with the concession obligations, the concessionaries have also the responsibility to provide technical management of the infrastructure. The Grant supervises compliance with concession obligations including supervising technical inspections on site. 4. The verification activities carried out by the road operators The regulatory evolution in the infrastructure sector, promoted by the Italian Ministry of Infrastructure, has led to the release of “Guidelines for Risk Classification and Management of Existing Tunnels” (Tunnels Guidelines) outlined in the CSLLPP ministerial decree No. 247/2022 and the update of the “Guidelines for Risk Classification and Management of Existing Bridges” ( Bridge Guidelines) outlined in the CSLLPP ministerial decree No. 204/2022 (that refines, and surpasses the previous provisions of decree No. 578/2020) (CSLLPP, 2020, CSLLPP, 2022a, CSLLPP, 2022b). Bridge Guidelines are integrated with the operational instructions provided by ANSFISA in 2022 (ANSFISA, 2022, Viti et al., 2024, Renzi et al., 2023). The structural verification activities carried out by the road Operators are aligned with the above-mentioned Guidelines, which represent a substantial evolution of the structure management model in terms of inspection procedures as well as frequency. In particular, the guidelines call for different levels of analysis, according to a multi-level approach, with an increasing degree of depth and detail. The aim of this method is to define an order of priority for the deepening of the investigations / checks / controls as well as for the planning of the necessary maintenance and structural interventions, under the responsibility of the road Managers. The central focus of the approach is the determination, for each bridge or tunnel, of the so- called “Overall attention class” that derives from the combination of partial attention classes, defined for bridges and tunnels. Combining the results in terms of (partial) class of attention, an overall class of attention can be assigned to the bridge or tunnel under examination according to different levels of increasing risk: low, medium-low, medium (only for bridges), medium-high and high. This multilevel method, delineated by Buratti et al. (2022) and illustrateed by Santarsiero et al. (2021) and Cutrone et al. (2023) varies from other prior BMSs developed by local authorities in Italy, (Bortot et al., 2006, Zonta et al., 2007, Yue, 2013, Capogna, 2023, Fattorini, 2023), and is comparable to Hazus bridge classification method (FEMA,2022). On this result, the bridge or tunnel owner or concessionary is required to adopt some consequent measures. In the case of a medium-low or low class of attention, the bridge or tunnel can hold its serviceability by undergoing the usual periodic inspections. In other cases, more in-depth safety evaluations are required to decide related to either possible traffic load reduction measures or retrofit interventions. Therefore, the Managers have the responsibility of the assessment and management of risks, the deterministic and analytical analysis of the safety of road infrastructure, including instrumental investigations, checks and controls and accurate safety assessments, as well as any consequent risk mitigation actions and/or necessary safety interventions, which must have a technical-scientific basis. 5. Supervision activities of the Directorate-General for Road and Highway infrastructures (DG-ISA) In order to improve the safety of road infrastructures, the DG- ISA’s mission is to promote the adoption of integrate Safety Management System (SMSs) ( so called “horizontal rule” ) for verification and maintenance of assets by the managers of the read and highway networks assets (so- called “vertical rules”). ANSFISA established a new guideline to define new SMSs for road infrastructures, that will be certified by third part bodies and will relate with the vertical rules constituted by innovative Italian Guidelines on risk management of existing bridges and tunnels (De Bartolomeo et al., 2022). Additionally, the Italian legislator entrusted ANSFISA with the task of ensuring the supervision of the safety conditions of the road and highway infrastructures, on the basis of an annual program of activities (Art. 12 paragraph 5-bis, of the Law-Degree No. 109/2018), of system audits, field inspections and random checks , thereby compelling the managing entities, who are responsible for their safe operation, to implement the necessary risk control measures