Evaluation of liquefaction triggering potential in Italy: a seismic-hazard-based approach

Abstract

Abstract. In the present study, we analyze ground-motion hazard maps and hazard disaggregation in order to define areas in Italy where liquefaction triggering due to seismic activity can not be excluded. To this end, we refer to the triggering criteria (not to be confused with liquefaction susceptibility criteria, which essentially take into account soil type and depth to groundwater) proposed by the Italian Guidelines for Seismic Microzonation, which are described in the main body of the paper. However, the study can be replicated in other countries that adopt different criteria. The final goal is the definition of a screening map for all of Italy that classifies sites in terms of liquefaction triggering potential according to their seismic hazard level. The map, which is referred to with the Italian acronym MILQ – Mappa del potenziale d'Innesco della LiQuefazione (i.e., map of liquefaction triggering potential), and the associated data are freely accessible at the following web address: https://distav.unige.it/rsni/milq.php (last access: 28 April 2023). Our results can be useful to guide land-use planners in deciding whether liquefaction is a hazard that needs to be considered within the planning processes or not. Furthermore, they can serve as a guide for recommending geological and geotechnical investigations aimed at the evaluation of liquefaction hazards or, conversely, rule out further studies with consequent savings in efforts and money.