Abstract
Abstract. Probabilistic estimates of seismic hazard represent a basic element for seismic risk reduction strategies and they are a key element of seismic regulation. Thus, it is important to select the most effective estimates among the available ones. An empirical scoring strategy is described here and is applied to a number of time-independent hazard estimates available in Italy both at national and regional scale. The scoring test is based on the comparison of outcomes provided by available computational models at a number of accelerometric sites where observations are available for 25 years. This comparison also allows identifying computational models that, providing outcomes that are in contrast with observations, should thus be discarded. The analysis shows that most of the hazard estimates proposed for Italy are not in contrast with observations and some computational models perform significantly better than others do. Furthermore, one can see that, at least locally, older estimates can perform better than the most recent ones. Finally, since the same computational model can perform differently depending on the region considered and on average return time of concern, no single model can be considered as the best-performing one. This implies that, moving along the hazard curve, the most suitable model should be selected by considering the specific problem of concern.
Highlights
Seismic hazard assessment is a basic tool for risk estimates necessary to develop effective preventive strategies against seismic damage
PSHA outcomes have the form of a peak ground acceleration (PGA) value g0 characterized by a fixed exceedance probability in a time span of duration t at the sth site
The best-performing model is the 1996 GNDT model at intermediate return time (ID1, RT = 284 years) followed by the MPS04-like area-based source model using Cauzzi and Faccioli (2008) ground motion prediction equation (GMPE) (ID5) for a 984 year return period; notably, models obtained under different theoretical assumptions or computational choices behave nearly the same: as an example one can see the results provided by the ID6 model, the ID5 one, and ID9
Summary
Seismic hazard assessment is a basic tool for risk estimates necessary to develop effective preventive strategies against seismic damage. Being in essence a forecasting of future ground shaking, uncertainty is a basic element of seismic hazard and it requires specific formalizations based on a probabilistic assumptions (probabilistic seismic hazard assessment – PSHA) to manage available information by providing likelihood estimates for each possible ground-shaking level (hazard curve). Information considered for this purpose includes deterministic (e.g. geometry of seismogenic structures or seismic waves propagation patterns) and statistical (e.g. average seismicity rates) elements. The data used in this study are given as Supplement to motivate alternative analyses and/or methodological comparisons
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
