An inter-disciplinary and multi-scale approach to assess the spatial variability of ground motion for seismic microzonation: the case study of Cavezzo municipality in Northern Italy

Seismic microzonation represents a basic tool for prevention activity planning and land management. An extensive and detailed microzonation study was performed
with reference to the territory of the Municipality of Cavezzo, damaged during the seismic sequence hitting Emilia-Romagna Region, Northern Italy, in 2012. In this
paper, we discuss the work carried out to characterize the spatial variability of ground motion amplification due to local soil conditions in the municipality area.
An inter- and multi-disciplinary approach is presented, involving geotechnical engineers, geophysicists, geologists and seismologists from different institutions, to
thoroughly characterize the territory using complementary techniques with different level of resolution and confidence. A considerable amount of geomorphological,
geological, hydrogeological, seismological, geotechnical and geophysical investigations was collected and processed for the purpose. A GIS-based (Geographic
Information System) platform was initially setup to manage the gathered data, which now includes the results of about 1000 geotechnical and geophysical tests. Such
an extended dataset was then used as a primary constraint for the creation of a comprehensive pseudo-3D geotechnical and seismo-stratigraphic model of the
territory, consisting of a dense grid of one-dimensional vertical profiles to depict the variability of the soil properties over the area. The model was finally used as
input for linear-equivalent ground response analysis. For the calculation of the amplification factors, special emphasis was given to the treatment and propagation of
the uncertainties of the model parameters, whose different realizations have been accounted through a logic tree approach.