AASHTO promulgated specifications for the design of mechanically stabilized earth (MSE) walls that define the characteristics of both the galvanized steel reinforcements and the backfill soils to be used in MSE wall construction. Although a few cases of poor performance have been documented, these occurrences are always correlated with a corrosive environment attributed to backfill or to site conditions that do not conform to the current design specifications. Data demonstrate that when good design and construction practices, as prescribed by AASHTO, are followed, the performance of metallic reinforcements exceeds current expectations for service life performance. The data also demonstrate that the current AASHTO metal loss model is unnecessarily conservative and that the AASHTO specifications should be revised to reflect documented in situ performance. To support this conclusion, the performance of galvanized steel reinforcements documented from nearly 150 observations distributed among 75 different sites throughout the United States and Europe are described, and these data are used as a basis to evaluate the metal loss model in the current AASHTO specifications.
Get full access to this article
View all access options for this article.
References
1.
RomanoffM.Underground Corrosion.National Bureau of Standards, Circular 579, U.S. Department of Commerce, 1957.
2.
Terre Armée Internationale (TAI).Durability of Reinforcing Strips. Report R50. TAI, Paris, France, 1977.
3.
Terre Armée Internationale (TAI).Container Test Results at the Thirteen-Year Stage. Report No. 10. TAI, Paris, France, 1990.
4.
DarbinM., JaillouxJ. M., MontuelleJ.. Durability of Reinforced Earth Structures: The Results of a Long-Term Study Conducted on Galvanized Steel.Institution of Civil Engineers (Great Britain) Proceeding, Part 1, Design and Construction, Vol. 84, 1988, pp. 1029–1057.
5.
EliasV.Durability/Corrosion of Soil Reinforced Structures. Report No. FHWA-RD-89-186. Office of Engineering and Highway Operations, R&D, McLean, Va., 1990.
6.
RehmG.The Service Life of Reinforced Earth Structures from a Corrosion Technology Standpoint.Expert Report. The Reinforced Earth Company, Vienna, Va., 1980.
7.
AASHTO. Task Force 27-AASHTO-AGC-ARBTA. Ground Modification Techniques for Transportation Applications.AASHTO, Washington, D.C., 1990.
Volume 01.06, Coated Steel Products.ASTM, West Conshohocken, Pa., 2004.
10.
Frondistou-YannisS.Corrosion Susceptibility of Internally Reinforced Soil Retaining Structures. Report No. FHWA/RD-83/105. National Technical Information Service, Springfield, Va., 1985.
11.
McGeeP.Reinforced Earth Wall Strip Serviceability Study. Final Report. Study No. 8405. Georgia Department of Transportation, Atlanta, 1985.
12.
RamaswamyS. D., and DiMillioA. F.. Corrosion in Reinforced Soil Structures.Public Roads.U.S. Department of Transportation, FHWA of R&D, Washington, D.C., 1986, pp. 43–48.
13.
WhitingD.Corrosion Susceptibility of Reinforced Earth Systems: Field Surveys.Corrosion Effect of Stray Currents and the Techniques for Evaluating Corrosion of Rebars in Concrete (ChakerV., ed.). ASTM STP 906. ASTM, Philadelphia, Pa., 1986, pp. 64–77.
14.
Standard Specifications for Transportation Materials and Methods of Sampling and Testing, 20th ed.AASHTO, Washington, D.C., 2002.
15.
DeaverR.Mechanically Stabilized Earth Wall Study. Final Report, GDOT Research Project No. 9001. Office of Materials and Research, Georgia Department of Transportation, Forest Park, 1992.
16.
MedfordW. M.Monitoring Corrosion of Galvanized Earth Wall Reinforcement. Presented at 78th Annual Meeting of the Transportation Research Board, Washington, D.C., 1999.
17.
BlightG. E., and DaneM. S. W.. Deterioration of a Wall Complex Constructed of Reinforced Earth.Geotechnique, Vol. 39, No. 1, 1989, pp. 47–53.
18.
WheelerJ. J.NYSDOT, MSES Corrosion Evaluation Program, End of the Year Report for 1998., NYSDOT Geotechnical Engineering Bureau, Albany, 1999.
19.
WheelerJ. J.Jr.New York's Mechanically Stabilized Earth System Corrosion Evaluation Program. Presented at 81st Annual Meeting of the Transportation Research Board, Washington, D.C., 2002.
20.
BerkovitzB. C., and HealeyE. A.. A Rational Process for Corrosion Evaluation of Mechanically Stabilized Earth Walls. In Mechanically Stabilized Backfill (J. T. Wu, ed,), Balkema, Rotterdam, The Netherlands, 1997, pp. 259–287.
21.
FishmanK. L., SalazarJ. M., and HilfikerH. K.. Corrosion in an Arid Environment and Condition Assessment of 20-Year-Old Mechanically Stabilized Earth Walls. Presented at 85th Annual Meeting of the Transportation Research Board, Washington, D.C., 2006.
22.
Service Life, Allowable Reinforcement Stress and Metal Loss Rates to be Used in the Design of Permanent MSE Structures. Technical Bulletin: MSE-1. The Reinforced Earth Company (RECO), Vienna, Va., 1992.
23.
AndersonP. L., and SankeyJ. E.. The Performance of Buried Galvanized Steel Earth Reinforcements After 20 Years in Service.Earth Reinforcement Practice: Proceedings of the International Symposium of Earth Reinforcement Practice (OchiaiH., HayasashiS., and OtaniJ., eds.). Balkema, Rotterdam, The Netherlands, 2002.
24.
RossiJ. P.The Corrosion Behavior of Galvanized Steel in Mechanically Stabilized Earth Structures. M.S. thesis. Department of Civil and Environmental Engineering, University of South Florida, Tampa, 1996.
25.
SaguesA. A., RossiJ., ScottR. J., PenaJ. A., and SimmonsT.. 1998. Influence of Corrosive Inundation on the Corrosion Rates of Galvanized Tie Straps in Mechanically Stabilized Earth Walls. Final Report WPI0510686. Florida Department of Transportation Research Center, Tallahassee, 1998.
26.
SaguesA., ScottR., RossiJ., PenaJ. A., and PowersR.. Corrosion Performance of Galvanized Strips in Florida Mechanically Stabilized Earth Walls. Presented at 78th Annual Meeting of the Transportation Research Board, Washington, D.C., 1999.
27.
TechnologiesCC. Monitoring of Instrumented MSE Wall, Contract No. D257956 (E 225-01) Item 17554.99M. Report Submitted to NYSDOT, 2000.
