PSI - Issue 78

Marco Civera et al. / Procedia Structural Integrity 78 (2026) 1783–1790

1786

Table 1. Corrective factors proposed for accounting of medium- to long-term effects post-event. Description Expected reopening time range

Assumed average value Corrective factor [-]

Minor (DS1; Superficial/Serviceable Damage). Quick repairs may include patching, sealing cracks, or minor realignment Moderate Damage (DS2; Functionally Impaired, slight to moderate structural damage). Repairs may involve strengthening structural elements, replacing damaged components, and ensuring safety through temporary supports Severe Damage (DS3; Non-Serviceable, moderate to heavy structural damage). The RN may not be safe to use without major repairs or temporary structural reinforcements. Extensive repair work, including rebuilding damaged supports and replacing large structural elements, is needed. Very severe damage (DS4; even partial collapse). Large portions of the asset (bridge or buildings) have collapsed. Debris removal and extensive (total or partial) reconstruction works are required Total collapse (DS5). The asset has totally collapsed or suffered catastrophic, irremediable damage. Dismantling, removal of debris, and total reconstruction are needed. (non-structural) Damage

Hours to a few days

1.5 days (36 hours) 1 week (168 hours)

1.000

Several days to a few weeks

36/168= 0.214

36/730= 0.049

Several weeks to a few months

1 month (730 hours on average)

36/4380= 0.008

Several months to a few years

6 months (4380 hours)

36/17,520= 0.002

Several years

2 years (17,520 hours)

To assess this corrected framework, the same investigation performed as in Case #2 of (Miano et al. 2024) is here re-proposed, again using two seismic events (moderate, Sc50, and elevate, Sc475) but considering all DSs (1 to 5) for both cases in lieu of the previous assumptions. As an important caveat, if the simulations return no evidence of damage occurring at that DS, the results are discarded. Without repeating too much of what is fully reported in (Miano et al. 2024), the case study of interest here is an example of a suburban RN, mainly gravitating on the Strada Statale (SS) 10, which connects the urban area of Turin to surrounding municipalities (Chieri and Pino Torinese). Four paths have been considered here, using SS10 or an alternative road (Strada del Pino Vecchio) and crossing the Po River at two distinct points. In total, the RN includes fifteen bridges (two river crossings and 13 viaducts, one of which is an overpass over SS10 from a secondary road). Importantly for all the considerations made in the previous work and here, the area has a low seismic hazard. 4. Results To begin with, the maximum efficiency value, reported as a straight solid red line in all following Figures, was calculated as , =0.64 - obviously, the same value is also reported in (Miano et al., 2024). Below, the results are firstly presented and commented upon for Sc475 in more detail; instead, the corresponding results for Sc50 are finally discussed in the last Subsections. 4.1. Damage State 1 (DS1) In the first case, shown in Figure 1.a, the (uncorrected) mean efficiency index stabilises around =0.28 after 2000 simulations. If one compares it to the , , it shows that the uncorrected efficiency has been reduced by more than 56%. As this is DS1, following what is proposed in Table 1, the corrected and uncorrected values are identical (since the corrective factor is equal to 1). In any case, one can see that the efficiency is very low, because the probability of reaching this amount of damage is very likely, even if the consequences in the medium to long run are very limited and can be easily recovered.