Location
New York, New York
Date
16 Apr 2004, 1:30pm - 3:30pm
Abstract
The construction of the road fixed-link crossing between Preveza and Aktio on the north-western coast of Greece has recently been completed. The project consists of an immersed single-tube tunnel under the strait and two cut-and-cover tunnels at the ends of the immersed part. The immersed section is constructed of eight precast rectangular concrete elements placed on the sea bottom at a depth of 25 m. The site is characterized by high seismicity. Foundation soil consists of Holocene marine sediments comprising irregular layers of sands, silts and clays that extend to great depth in the central part of the strait. Along the entire tunnel alignment the silty sands and sandy silts of the top layers are classified as potentially liquefiable due to their low density. Soil improvement in the form of stone columns has been carried out below the tunnel foundation for reducing risk from liquefaction. The soil conditions and the seismic input parameters are presented and an overview of the extensive dynamic laboratory testing program conducted is given. The seismic site response analyses performed for determining the depth of ground improvement are summarized. The design of the stone columns as well as a practical method for estimating the stiffness of the composite soil are described.
Department(s)
Civil, Architectural and Environmental Engineering
Meeting Name
5th Conference of the International Conference on Case Histories in Geotechnical Engineering
Publisher
University of Missouri--Rolla
Document Version
Final Version
Rights
© 2004 University of Missouri--Rolla, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Document Type
Article - Conference proceedings
File Type
text
Language
English
Recommended Citation
Vrettos, Christos and Savidis, Stavros, "Stone Column Ground Improvement Against Liquefaction for the Preveza-Aktio Immersed Tunnel" (2004). International Conference on Case Histories in Geotechnical Engineering. 15.
https://scholarsmine.mst.edu/icchge/5icchge/session12/15
Stone Column Ground Improvement Against Liquefaction for the Preveza-Aktio Immersed Tunnel
New York, New York
The construction of the road fixed-link crossing between Preveza and Aktio on the north-western coast of Greece has recently been completed. The project consists of an immersed single-tube tunnel under the strait and two cut-and-cover tunnels at the ends of the immersed part. The immersed section is constructed of eight precast rectangular concrete elements placed on the sea bottom at a depth of 25 m. The site is characterized by high seismicity. Foundation soil consists of Holocene marine sediments comprising irregular layers of sands, silts and clays that extend to great depth in the central part of the strait. Along the entire tunnel alignment the silty sands and sandy silts of the top layers are classified as potentially liquefiable due to their low density. Soil improvement in the form of stone columns has been carried out below the tunnel foundation for reducing risk from liquefaction. The soil conditions and the seismic input parameters are presented and an overview of the extensive dynamic laboratory testing program conducted is given. The seismic site response analyses performed for determining the depth of ground improvement are summarized. The design of the stone columns as well as a practical method for estimating the stiffness of the composite soil are described.
