CPT-Based Liquefaction Case History from the 2012 Emilia Earthquake in Italy

Significant and widespread liquefaction phenomena were observed after the main shock of the Emilia earthquake (Italy) on May 20, 2012. A number of statistically independent CPT-based liquefaction field case histories were selected by the authors, the critical layer towards liquefaction was identified, and the liquefaction resistance parameter and loading parameter were assessed. Key parameters for each site and critical layer were provided to be added to a select larger and worldwide liquefaction case history database proposed by other authors for estimating CPT-based liquefaction triggering resistance curves. Finally, applicability to the case study of some more widely used CPT-based simplified approaches was tested. A systematic underestimation of liquefaction potential was found and is discussed, possible reasons are explored, and suggestions are proposed.