Restricted Research - Award List, Note/Discussion Page

Fiscal Year: 2018

1115  The University of Texas at El Paso  (74620)

Principal Investigator: Soheil Nazarian

Total Amount of Contract, Award, or Gift (Annual before 2011): $ 364,999

Exceeds $250,000 (Is it flagged?): Yes

Start and End Dates: 9/1/17 - 8/31/18

Restricted Research: YES

Academic Discipline: Civil Engineering

Department, Center, School, or Institute: Center for Transportation Infrastructure Systems

Title of Contract, Award, or Gift: OR20150524A 226370005A Implementation of New Specification Requirements for Coarse Backfill Materials for Mechanically Stabilized Earth (MSE) Walls

Name of Granting or Contracting Agency/Entity: Texas Department of Transportation
CFDA Link: DOT
20.205

Program Title: Highway Planning and Construction
CFDA Linked: Highway Planning and Construction

Note:

Qualifies under SAM 1.1.1. 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. Testing demonstrated that the fines collected from the field were enriched in chemicals that when exposed to water decreased pH and resistivity and increased chloride or sulfate concentrations relative to the bulk rock. This phenomenon can bias traditional soil testing results and therefore the assessment of corrosion potential. A more representative and appropriate geochemical testing protocol is recommended by TxDOT research project 0-6359. The objective of this implementation project is to establish material specifications for coarse aggregates (Item 423, Type A and D) used to construct MSE walls in Texas.

Discussion:

1.1.1
yes 8.1.18jn

 

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