Reanalysis of the settlement of a levee on soft bay mud

Staged construction of embankments on soft ground remains one of the most challenging topics in geotechnical engineering due to the complex shear and consolidation behavior of clays. This thesis presents a case study on the performance of the New Hamilton Partnership (NHP) levee in Novato, California. This 11ft high levee was constructed over 30 ft - 40 ft thick layer of San Francisco Bay Mud during a six-month period in 1996. Settlements along the levee crest were monitored over a period of 5.2 years after the end of construction (until early 2002), at which time URS installed piezometers to measure the existing consolidation stresses (s'vc) within the Bay Mud. URS also conducted state-of-the art field and laboratory test programs to develop well-defined values of preconsolidation stress (s'p) and compressibility parameters for the Bay Mud. However, conventional 1-D consolidation analyses greatly underestimated the measured levee settlements. Hence URS reduced s'p by 20% for the Plaxis FE analyses with the Soft Soil Model (SSM) used to replicate the performance of the existing NHP levee and then to design an expanded levee system. This thesis presents a detailed re-evaluation of the NHP levee performance and of the stress history, strength, and consolidation properties of the Bay Mud obtained during the URS geotechnical site investigation.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Civil and Environmental Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Nguyen, Hoang Q. (Hoang Quang)

Advisor dc:contributor.advisor

• Andrew J. Whittle and Charles C. Ladd.

• Civil and Environmental Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/38513

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/38513