Location
Arlington, Virginia
Date
15 Aug 2008, 11:00am - 12:30pm
Abstract
Coquitlam Dam, constructed in the early 1910s, is a 30 m high hydraulic fill embankment. The dam is situated in a region of high seismic hazard in British Columbia, Canada. The existing dam core and shells, and part of the dam foundation are deemed to be liquefiable under the design earthquake. A new 30 m high compacted earth core rockfill embankment dam is currently being constructed at the downstream toe of the existing dam. As part of the construction of the new dam, a seepage cutoff wall has been completed underneath the central core of the new embankment to control foundation seepage gradients and to minimize piping potential of the foundation soils. The wall was constructed of plastic concrete using slurry panel construction method. Plastic concrete was selected to provide a seepage cutoff wall that has sufficient strength to withstand both static and seismic stresses beneath the new embankment, and yet is flexible enough to undergo seismic deformations, without cracking, with the surrounding soils. This paper describes the construction of the plastic concrete cutoff wall for the new Coquitlam dam, including the field and laboratory testing performed to confirm design wall stiffness, strength, and hydraulic conductivity requirements. The trial laboratory and field testing programs to determine plastic concrete mix design, and the QA/QC testing conducted during construction, including measurement of in-situ hydraulic conductivity of the constructed plastic concrete panels, are presented.
Department(s)
Civil, Architectural and Environmental Engineering
Meeting Name
6th Conference of the International Conference on Case Histories in Geotechnical Engineering
Publisher
Missouri University of Science and Technology
Document Version
Final Version
Rights
© 2008 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
Yan, L.; Trapp, D. A.; and Sy, A., "Construction of a Plastic Concrete Seepage Cutoff Wall for the New Coquitlam Dam" (2008). International Conference on Case Histories in Geotechnical Engineering. 7.
https://scholarsmine.mst.edu/icchge/6icchge/session05/7
Construction of a Plastic Concrete Seepage Cutoff Wall for the New Coquitlam Dam
Arlington, Virginia
Coquitlam Dam, constructed in the early 1910s, is a 30 m high hydraulic fill embankment. The dam is situated in a region of high seismic hazard in British Columbia, Canada. The existing dam core and shells, and part of the dam foundation are deemed to be liquefiable under the design earthquake. A new 30 m high compacted earth core rockfill embankment dam is currently being constructed at the downstream toe of the existing dam. As part of the construction of the new dam, a seepage cutoff wall has been completed underneath the central core of the new embankment to control foundation seepage gradients and to minimize piping potential of the foundation soils. The wall was constructed of plastic concrete using slurry panel construction method. Plastic concrete was selected to provide a seepage cutoff wall that has sufficient strength to withstand both static and seismic stresses beneath the new embankment, and yet is flexible enough to undergo seismic deformations, without cracking, with the surrounding soils. This paper describes the construction of the plastic concrete cutoff wall for the new Coquitlam dam, including the field and laboratory testing performed to confirm design wall stiffness, strength, and hydraulic conductivity requirements. The trial laboratory and field testing programs to determine plastic concrete mix design, and the QA/QC testing conducted during construction, including measurement of in-situ hydraulic conductivity of the constructed plastic concrete panels, are presented.
