Location
New York, New York
Date
14 Apr 2004, 4:30 pm - 6:30 pm
Abstract
Two, 42-meter diameter, 12.2 meter high (100,000 barrel) above ground jet fuel tanks are currently under construction by the Japan Engineering District (JED), U.S. Army Corps of Engineers for the Defense Logistic Agency (DLA) at Marine Corps Air Station (MCAS) Iwakuni. This presentation is a case study of the installation of Sand Compaction Piles (SCP’s) and surcharge at MCAS Iwakuni. The geology below the tanks consists of poorly behaving liquefiable silty clays that can affect the bearing capacity of the loaded tanks. The site was formerly a marsh area filled with various debris and construction refuse and then covered with fill material. The elevation of the original marsh area is at sea level, and corresponds to the elevation of groundwater. The near surface soil consists of 6 to 12 meters of loose, liquefiable sand. Underlying this sand layer is 15 to 20 meters of soft, compressible clays and silts. A medium to dense sand and gravel underlies the soft clays and silts. The Iwakuni Faults, which are active faults, are located near MCAS Iwakuni. These faults are classified as Class B under the Japanese Standard, which is medium level in magnitude. The distance from MCAS Iwakuni to these faults is approximately 8 km. Foundation treatments to include SCP’s, Sand Drainage Piles (SDPs) and surcharge mounds are used to improve foundation conditions. SCPs are not a deep foundation as in a typical pile, but rather a method for dynamically densifying loose sands. They have used extensively in Japan for many years to decrease the potential for liquefaction damage. Effectiveness of the SCPs in densifying the surrounding soils is determined by measuring the “N” value determined from a Standard Penetration Test taken in the area between the SCPs. The clay layer was consolidated using a soil surcharge. Percent consolidation was determined using vibrating wire piezometers.
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
Taylor, Perry A. and Gerlach, John A., "Foundation Treatments Using Sand Compaction Piles and Surcharge Loading Marine Corps Air Station Iwakuni, Japan, A Case Study" (2004). International Conference on Case Histories in Geotechnical Engineering. 10.
https://scholarsmine.mst.edu/icchge/5icchge/session01/10
Foundation Treatments Using Sand Compaction Piles and Surcharge Loading Marine Corps Air Station Iwakuni, Japan, A Case Study
New York, New York
Two, 42-meter diameter, 12.2 meter high (100,000 barrel) above ground jet fuel tanks are currently under construction by the Japan Engineering District (JED), U.S. Army Corps of Engineers for the Defense Logistic Agency (DLA) at Marine Corps Air Station (MCAS) Iwakuni. This presentation is a case study of the installation of Sand Compaction Piles (SCP’s) and surcharge at MCAS Iwakuni. The geology below the tanks consists of poorly behaving liquefiable silty clays that can affect the bearing capacity of the loaded tanks. The site was formerly a marsh area filled with various debris and construction refuse and then covered with fill material. The elevation of the original marsh area is at sea level, and corresponds to the elevation of groundwater. The near surface soil consists of 6 to 12 meters of loose, liquefiable sand. Underlying this sand layer is 15 to 20 meters of soft, compressible clays and silts. A medium to dense sand and gravel underlies the soft clays and silts. The Iwakuni Faults, which are active faults, are located near MCAS Iwakuni. These faults are classified as Class B under the Japanese Standard, which is medium level in magnitude. The distance from MCAS Iwakuni to these faults is approximately 8 km. Foundation treatments to include SCP’s, Sand Drainage Piles (SDPs) and surcharge mounds are used to improve foundation conditions. SCPs are not a deep foundation as in a typical pile, but rather a method for dynamically densifying loose sands. They have used extensively in Japan for many years to decrease the potential for liquefaction damage. Effectiveness of the SCPs in densifying the surrounding soils is determined by measuring the “N” value determined from a Standard Penetration Test taken in the area between the SCPs. The clay layer was consolidated using a soil surcharge. Percent consolidation was determined using vibrating wire piezometers.
