GNGTS 2014 - Atti del 33° Convegno Nazionale

434 GNGTS 2014 S essione 2.3 back from the passage of the tip. For this reason, the lateral friction measured with the mechanical tip is always greater than that measured with the electric tip. This condition has negligible influence in the case of cohesive soils, while for sandy ones values up to 2 times higher than those measured with other tips or electric ones can be found (Lo Presti et al. , 2009). In order to better address the reconstruction following the May 2012 seismic sequence, and to favour a correct urban planning by the local administrations, microzonation studies are of utmost importance. Indeed the production of a series of maps able to identify the criticalities of the area in case of future seismic crisis represents a crucial step in this regard. On October 15, 2013, the Geological Survey of the Regione Emilia-Romagna had already provided a preliminary series of maps, through limited to the urbanized and potentially urbanized areas. Additionally, in the frame of a dedicated research project financed by the Municipality of Sant’Agostino, the Department of Physics and Earth Sciences of the University of Ferrara, has carried out an independent seismic microzonation study of the whole territory. However, it is noteworthy that the finally produced maps represent an agreed and shared product of interest for the local administration. In the maps are defined and highlighted the areas subject to possible instability phenomena, such as liquefaction and amplification of the seismic motion. The interest has been clearly manifested by the Municipality of Sant’Agostino by assuming the results of the microzonation study as a formal administrative document (“Quadro Conoscitivo”). Moreover, based on the produced maps, the Administration will further formally acknowledge the results of the study deliberating, in agreement with the designers responsible for the reconstruction project, new specific regulations for future planning and building within its territory. Fig. 3 – Map of the amplification factors and the liquefaction hazard of the Sant’Agostino Municipality, realized in the frame of the seismic microzonation study. In the background, the pink and orange colors refer to the value of the amplification factor. The red and gray cross-hatch symbologies delimit respectively the areas characterized by the presence of liquefiable horizons in the first 10 to 20 m. The colored squares and dots refer to the value of the Liquefaction Potential Index calculated respectively by electrical and mechanical penetration tests; in particular, the white color means low liquefaction hazard, while red one an elevated hazard.