Liquefaction hazard evaluation for a 3rd level microzonation study in a high seismicity area of Central Italy

Widespread liquefaction phenomena may also occur in surface alluvial intermediate soils composed of alternations of saturated sandy silts, silts, silty and clayey sands, during earthquakes of moderate magnitude as experienced for the 2012 Emilia Romagna seismic sequence. By the consequence, liquefaction hazard evaluation has been included in the most recent 3rd level microzonation studies promoted by some Regional Governments. The paper presents the results of one of those studies performed for the municipality of Barberino di Mugello that falls within a high seismicity area of Central Italy including typical Appennine intramontane basins where surface alluvial soil layers that overlay fluvio-lacustrine soil deposits can be frequently encountered. With reference to the studied area, the liquefaction potential and the expected settlements of intermediate soil deposits are calculated by using different simplified methods and the corresponding liquefaction hazard maps are presented and discussed.