Site characterization by seismic dilatometer (SDMT) in the city of L'Aquila

This paper presents a review of results obtained by a large number of seismic dilatometer tests (SDMT) carried out in the area
of L’Aquila (Central Italy), after the April 6th, 2009 earthquake. Due to the characteristics of the soils (mostly coarse-grained, nonpenetrable
materials), SDMT measurements were generally performed in backfilled boreholes, using the technique briefly described;
in these conditions only the shear wave velocity VS, without the other DMT parameters, was measured. The test results illustrated
in the paper include: (a) SDMT typical results obtained by the normal penetration procedure (in a limited number of sites, mostly
silts); (b) VS-only profiles obtained by the backfilled borehole procedure; (c) comparisons of VS profiles obtained by SDMT and by
other techniques (Down-Hole, Cross-Hole, surface waves tests); (d) comparisons of VS measured by SDMT and those estimated
from mechanical DMT data. The VS profiles provided by SDMT, combined with the information obtained from geological data and
from other investigations, including boreholes down to a maximum depth of 300 m in the city centre, have been used for the soil
characterization in numerical seismic response analyses. An example is illustrated in the paper.