Location
San Diego, California
Presentation Date
27 May 2010, 4:30 pm - 6:20 pm
Abstract
Ground displacements resulting from earthquake-induced soil liquefaction and dynamic densification can cause moderate to severe structural damage during and after an earthquake. Geotechnical construction methods of mitigating these potential ground displacements include mass excavation and replacement with engineered fill, ground improvement such as soil mixing, jet grouting, compaction piers, vibro compaction, vibro stone columns, and deep dynamic compaction, or deep foundations such as driven piles. The ground improvement methods rely on altering the soil properties to resist the seismically-induced shear stresses and soil grain redistribution while deep foundation methods bypass liquefiable soil deposits to found in deeper competent soil or rock. This paper presents an advancement in displacement ground improvement methods used to control soil liquefaction potential by driving highly compacted aggregate into the soil deposit. The ground improvement is accomplished by driving a pipe mandrel to displace the soil mass, backfilling the cavity with select aggregate, and compacting the aggregate in controlled lifts utilizing vertical, vibratory driven methods to further displace and densify the soil deposit while creating a dense Rammed Aggregate Pier®. Specifically the ground improvement method 1) reinforces the soil deposit to resist and re-distribute seismic shear stresses, 2) increases the density and horizontal stress of the surrounding soil, and 3) provides a gravel drain to enhance dissipation of seismicallyinduced excess pore water pressure in the soil. Several projects performed in California, in areas of high seismic activity, have been tested for the resulting shear reinforcement effects and increased density effects manifested by this advanced method of construction. These projects and their resulting field test results are presented and discussed.
Department(s)
Civil, Architectural and Environmental Engineering
Meeting Name
5th International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Publisher
Missouri University of Science and Technology
Document Version
Final Version
Rights
© 2010 Missouri University of Science and Technology, 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
Farrell, Tom M.; Wallace, Kyle; and Ho, John, "Liquefaction Mitigation of Three Projects in California" (2010). International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics. 25.
https://scholarsmine.mst.edu/icrageesd/05icrageesd/session04/25
Included in
Liquefaction Mitigation of Three Projects in California
San Diego, California
Ground displacements resulting from earthquake-induced soil liquefaction and dynamic densification can cause moderate to severe structural damage during and after an earthquake. Geotechnical construction methods of mitigating these potential ground displacements include mass excavation and replacement with engineered fill, ground improvement such as soil mixing, jet grouting, compaction piers, vibro compaction, vibro stone columns, and deep dynamic compaction, or deep foundations such as driven piles. The ground improvement methods rely on altering the soil properties to resist the seismically-induced shear stresses and soil grain redistribution while deep foundation methods bypass liquefiable soil deposits to found in deeper competent soil or rock. This paper presents an advancement in displacement ground improvement methods used to control soil liquefaction potential by driving highly compacted aggregate into the soil deposit. The ground improvement is accomplished by driving a pipe mandrel to displace the soil mass, backfilling the cavity with select aggregate, and compacting the aggregate in controlled lifts utilizing vertical, vibratory driven methods to further displace and densify the soil deposit while creating a dense Rammed Aggregate Pier®. Specifically the ground improvement method 1) reinforces the soil deposit to resist and re-distribute seismic shear stresses, 2) increases the density and horizontal stress of the surrounding soil, and 3) provides a gravel drain to enhance dissipation of seismicallyinduced excess pore water pressure in the soil. Several projects performed in California, in areas of high seismic activity, have been tested for the resulting shear reinforcement effects and increased density effects manifested by this advanced method of construction. These projects and their resulting field test results are presented and discussed.
