Location

New York, New York

Session Start Date

4-13-2004

Session End Date

4-17-2004

Abstract

The present study is part of a research programme, namely "Detailed Scenarios and Actions for Seismic Prevention of Damage in the Urban Area of Catania", financed by the National Department for the Civil Protection and National Research Council – National Group for the Defence Against Earthquake (CNR – GNDT). Among the objectives of the project there are in particular the geotechnical characterisation of soils of the city of Catania and the evaluation of site effects due to local site amplification phenomena. The investigation program was performed in seven different test areas of Catania. One of which is the "Plaja beach" sand site. The sand soil was also used to study soil-retaining wall interaction by means of the shaking table. These experiments require an accurate definition of geotechnical characterisation of soil. To define the mechanical behaviour of Catania sand a large number of static and dynamic laboratory tests were performed on dry reconstituted specimens. The static tests includes direct shear tests performed on specimens reconstituted by pluvial deposition method with different relative density Dr. To evaluate the equivalent shear modulus Geq and damping ratio D, resonant column tests were performed by mean of Resonant Column apparatus. Particular attention was devoted to the shear modulus at very small strain (γ < 10-3 %) where the soil behaviour is supposed to be elastic and at intermediate strain level (from 10-3 % to 0.5 %) for simulating the prefailure deformation during the shaking table tests. The behaviour of soil at intermediate strain level is relevant for the serviceability limit state according the European Codes (EC7 and EC8). Finally, two expressions to allow the complete shear modulus degradation with strain level and the inverse variation of damping ratio with normalised shear modulus respectively were proposed.

Department(s)

Civil, Architectural and Environmental Engineering

Appears In

International Conference on Case Histories in Geotechnical Engineering

Meeting Name

Fifth Conference

Publisher

University of Missouri--Rolla

Publication Date

4-13-2004

Document Version

Final Version

Rights

© 2004 University of Missouri--Rolla, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Dynamic Geotechnical Characterization for the Microzonation of the Seismic Area of Catania

New York, New York

The present study is part of a research programme, namely "Detailed Scenarios and Actions for Seismic Prevention of Damage in the Urban Area of Catania", financed by the National Department for the Civil Protection and National Research Council – National Group for the Defence Against Earthquake (CNR – GNDT). Among the objectives of the project there are in particular the geotechnical characterisation of soils of the city of Catania and the evaluation of site effects due to local site amplification phenomena. The investigation program was performed in seven different test areas of Catania. One of which is the "Plaja beach" sand site. The sand soil was also used to study soil-retaining wall interaction by means of the shaking table. These experiments require an accurate definition of geotechnical characterisation of soil. To define the mechanical behaviour of Catania sand a large number of static and dynamic laboratory tests were performed on dry reconstituted specimens. The static tests includes direct shear tests performed on specimens reconstituted by pluvial deposition method with different relative density Dr. To evaluate the equivalent shear modulus Geq and damping ratio D, resonant column tests were performed by mean of Resonant Column apparatus. Particular attention was devoted to the shear modulus at very small strain (γ < 10-3 %) where the soil behaviour is supposed to be elastic and at intermediate strain level (from 10-3 % to 0.5 %) for simulating the prefailure deformation during the shaking table tests. The behaviour of soil at intermediate strain level is relevant for the serviceability limit state according the European Codes (EC7 and EC8). Finally, two expressions to allow the complete shear modulus degradation with strain level and the inverse variation of damping ratio with normalised shear modulus respectively were proposed.