Shear Modulus and Damping of a Stiff Clay from in Situ and Laboratory Tests

This paper describes and compares the results of in situ and laboratory investigations which were carried out in order to determine the soil profile of the Saline di Augusta site (also Saline site), with special attention being paid to the variation of shear modulus and damping ratio with depth. The soil deposits at this site mainly consist of a medium stiff, overconsolidated (OCR = 2.0 to 6.0), Pleistocene marine clay with low to medium PI, overlaid by a 15 m thick Holocene silty clay stratum. The Saline site is located near the city of Augusta on the east coast of Sicily which is one of the most seismically active areas of Italy.