Case Study: Condition Assessment of a 36-Year-Old Mechanically Stabilized Earth Wall in Virginia
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 143, Issue 5
Abstract
In 2012, a mechanically stabilized earth (MSE) wall was demolished in Virginia due to road realignment activities, providing an opportunity to assess the condition of the steel-bar mat reinforcement after 36 years in service. Steel and backfill samples were collected from various locations throughout the wall. The remaining zinc thickness from the galvanized steel was measured utilizing three different techniques; the electrochemical properties of the backfill were also measured. It was found that corrosion was highest at the joint between the pavement and moment slab and in locations downstream of a drainage pipe through the wall. By industry design standards, the electrochemical properties of the backfill, specifically the chlorides and resistivity, indicate the backfill collected is aggressive; however, the wall was in good condition, with an estimated service life of 150 years based on the measured corrosion. This article provides an overview of this case study, the testing performed, and the results; it also examines methods to estimate initial thickness of the zinc coating for insights on the performance of galvanized steel used in earthwork applications.
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Acknowledgments
The authors would like to extend their appreciation to Chris Dumas (with CH2M HILL) for his initial coordination efforts between FHWA and Fluor Corporation to perform sample collection. Appreciation is also given to former FHWA interns Jeff Lin and Daniel Powers for help with sample collection; former intern Kerry McCaffrey, along with full-time staff at Turner-Fairbank Highway Research Center, including Thomas Gebrenegus, Terry Arnold, Rongtang Liu, Paul Virmani, and Jason Provines also provided assistance in sample testing. The authors also gratefully acknowledge Ken Fishman, Daniel Alzamora, Rich Barrows, and Fassil Beshah for providing technical expertise on this project.
References
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 143 • Issue 5 • May 2017
Copyright
©2016 American Society of Civil Engineers.
History
Received: Dec 1, 2015
Accepted: Sep 19, 2016
Published online: Nov 30, 2016
Discussion open until: Apr 30, 2017
Published in print: May 1, 2017
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