PSI - Issue 44

Manuel Capogna et al. / Procedia Structural Integrity 44 (2023) 705–712 Manuel Capogna et al./ Structural Integrity Procedia 00 (2022) 000–000

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1. Introduction The Italian Bridge Guidelines (MIMS, 2020) provide for a multilevel classification approach: • Geolocation and census of the bridges (Level 0) • Execution of visual inspections and filling up defects’ forms (Level 1) • Determination of the attention class of the bridge (Level 2) • The preliminary safety assessment (Level 3) • Detailed safety assessment (Level 4) • Resilience assessment of the road network (Level 5)

Fig. 1. Italian Bridge Guidelines multilevel approach (MIMS, 2020).

Level 2 represents the central focus of the approach, the results of which depend on the measures and therefore the application of subsequent levels of analysis. The classification method provides for the determination, for each bridge, of the so-called “Overall Attention Class”. It is the result of the combination of 4 distinct Attention Classes (AC) linked to 4 different types of risk - structural and foundational risk, seismic risk, landslide risk and hydraulic risk. The determination of each Attention Class is the result of the combination of hazard, vulnerability and exposure factors. However, logical classes and operators are used for its determination, while numerical indices or operations aimed at determining risk indices never appear. The overall attention class therefore represents an approximate estimate of the risk factors, useful for defining an order of priority for the deepening of investigations / checks / controls as well as for planning the necessary maintenance and structural interventions, but without being able to reach the accuracy of the results of a comprehensive risk analysis. This multilevel approach is similar to other bridge classification methods such as those present in Hazus, initially developed by FEMA for seismic risk in 1997 and then extended from 2004 to a multi-hazard version (FEMA,2022). Hazus risk analyses are categorized as Basic (Level 1) or Advanced (Levels 2 and 3), depending on the level of effort and expertise required by the user. Advanced analyses incorporate more detailed local asset data to generate more accurate results. In this work the seismic attention class will be studied in depth in order to create an automatic calculation prototype that can be used both in cloud and standalone desktop/server applications.