1D non-linear seismic response analysis of soft soil deposits

This paper focuses on the stratigraphic effects and describes the results of 1D non-linear seismic response analyses carried out using the computer code Deepsoil vs. 6.1. A set of ideal profiles of soft soil deposits, belonging to the soil class C according to Eurocode 8 and Italian seismic regulation, were considered varying the bedrock depth H and the average shear wave velocity VS,H and assuming a complaint bedrock. The parameters defining the backbone curve have been calibrated using shear modulus reduction curves available in the literature for soils of low to medium plasticity. A set of horizontal acceleration time histories, recorded on stiff horizontal outcropping bedrock, with peak values in the range 0.044g-0.279g are used as input motions. The analysis results were presented in terms of peak acceleration and acceleration amplification ratio at the ground surface and are compared with a large set of data concerning field and numerical data.