PSI - Issue 78

Marco Faggella et al. / Procedia Structural Integrity 78 (2026) 2141–2146

2144

5. NTC18 Time-adaptive Reliability The interplay between earthquake and drought risk can be modelled comparing the Lower Bound Water Loss scenario curve, with the Upper Bound Earthquake PSHA. This is done changing the Earthquake PSHA lines according to decreased or increased vulnerability, for example down to the 30% PGA reduction, as found in the sub facilities assessment contracted by Autorità di Bacino and published in 2025.

Fig. 2. NTC18 PSHA and Multi-risk Time-adaptive decision framework in (a) regular plot, and (b) log plot.