Implementation of New Specification Requirements for Coarse Backfill Materials for Mechanically Stabilized Earth (MSE) Walls

The service life of mechanically stabilized earth (MSE) walls depends on the rate of corrosion of the metallic reinforcements used in their construction. Assessment of corrosion potential requires the accurate evaluation of pH, resistivity, and ionic (e.g., sulfate and chloride) concentrations of aqueous solutions in contact with the surrounding aggregate. There is a tendency to utilize larger-size aggregates that contain only a small amount of fine material (passing No. 40 sieve) in the backfill. Evaluation of the electrochemical parameters of coarse aggregates is challenging because traditional methods utilize only fine-grained material. Under Project 0-6359 entitled “Characterization of Backfill Materials for Prevention of Corrosion of MSE Metallic Wall Reinforcement,” more representative geochemical testing protocols were recommended for the consideration by Texas Department of Transportation (TxDOT). Based on the promising results from that study, this follow on study was carried out to standardize the test protocols and provide specifications that TxDOT personnel can readily use the proposed methods. The outcome of this study is two standards that can potentially supplant the test procedures for resistivity (Tex-129-E); pH (Tex128-E), Chloride and Sulfate (Tex-620-J) of the backfill materials. Based on testing more than two dozen backfill materials collected from throughout Texas, these methods seem to be more representative and more practical than the current tests especially for the coarser backfills.

• Record URL:
  https://library.ctr.utexas.edu/hostedpdfs/utep/5-6359-01-1.pdf
• Summary URL:
  https://library.ctr.utexas.edu/Presto/catalogid=39557
• Summary URL:
  https://library.ctr.utexas.edu/Presto/catalogid=39558
• Record URL:
  https://rosap.ntl.bts.gov/view/dot/58957
• Supplemental Notes:
  • Submitted August 2018; published September 2021.
• Corporate Authors:

  University of Texas, El Paso

  Center for Transportation Infrastructure Systems
  500 W University Avenue
  El Paso, TX  United States  79968-0516

  Texas Department of Transportation

  Research and Technology Implementation Office
  125 E 11th Street
  Austin, TX  United States  78701-2483

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Arciniega, Jose Luis
  • Cabrera, Diana
  • Svede, Troy
  • Rocha, Sergio
  • Garibay, Jose
  • Walker, W Shane
  • Bronson, Arturo
  • Nazarian, Soheil
• Publication Date: 2021-9

Language

• English

Media Info

• Media Type: Digital/other
• Features: Appendices; Figures; Maps; Photos; Tables;
• Pagination: 46p

Subject/Index Terms

• TRT Terms: Backfilling; Coarse aggregates; Corrosion; Mechanically stabilized earth; Specifications; Test procedures
• Geographic Terms: Texas
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 01784394
• Record Type: Publication
• Report/Paper Numbers: FHWA/TX-18/5-6359-01-1, 5-6359-01-1
• Contract Numbers: 5-6359-01
• Files: NTL, TRIS, ATRI, USDOT, STATEDOT
• Created Date: Oct 7 2021 4:58PM