Liquefied sites of the 2012 Emilia earthquake: a comprehensive database of the geological and geotechnical features (Quaternary alluvial Po plain, Italy)

This paper presents a comprehensive geological and geotechnical study of the whole area
affected by liquefaction following the 2012 Emilia earthquakes, including all the available
information from the field reconnaissance surveys, in situ tests, and laboratory analyses.
The compilation was performed at 120 liquefied sites to verify and validate the reliability
of liquefaction charts in alluvial sediments, and to assess liquefaction induced by the 2012
seismic sequence in the Emilia plain. The results reveal a wide range of grain sizes (from
clean sands to sandy silts) and compositional characteristics (quartz-rich to litharenitic) in
the 2012 ejecta, and show a strong relationship between the liquefaction and stratigraphic
architecture of the subsurface. The availability of in situ tests at the liquefied sites makes
it possible to verify and validate the reliability of the liquefaction charts in alluvial sediments
with respect to the real observations. For the analyzed Emilia case studies, the use
of non-liquefiable crust provides better estimations of the liquefaction manifestations when
coupled with the thickness of the liquefiable layer rather than with the liquefaction potential
index. Altogether, this work makes available to the international scientific community a
consistent liquefaction database for in-depth earthquake studies