Publication Preview Source Site response analyses for seismic microzonation: Case-histories, results and applications in Central Italy

The paper presents the main results of 1D/2D site response numerical analysesat 4 sites selected among the 137 municipalities of the Seismic Microzonation study which hasbeen carried out after the 2016 Central Italy seismic sequence. Complex site effects at ridge/slope crest and at the edge of slope covers lead to 2D aggravation factors in the range 2-3 withrespect to ground motion predicted with simple 1D analyses. A systematic comparison carriedout for all 137 municipalities, between computed and Italian code NTC18 amplification fac-tors highlighted that the code is generally conservative at low-to-medium periods and over-conservative at medium-to-high periods. A strategy for the use of microzonation site responseanalyses in support of seismic design for the reconstruction process is finally suggested .