Sources and Substitutes for Fly Ash in Concrete

Details

• Creators:
  Mobasher, Barzin ; Neithalath, Narayanan ; Ramirez, Barbara
• Corporate Creators:
  Arizona State University. School of Sustainable Engineering and the Built Environment
• Corporate Contributors:
  Arizona. Department of Transportation ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  Admixtures Cement Concrete Fly Ash Mix Design
• Publication/ Report Number:
  SPR-780
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Arizona
• Edition:
  Final Report
• Corporate Publisher:
  Arizona. Department of Transportation
• Abstract:
  Fly ash, a by-product of coal combustion, improves the workability, mechanical properties, durability, and sustainability of concretes when added as a supplement. Dwindling supplies of fly ash led Arizona DOT (ADOT) to investigate the use of alternative cementitious materials (ACMs) in concrete mixture designs. This study drew from a review of literature, a survey of state practice among state departments of transportation (DOTs), and the authors’ own research and past experience. The report details currently available alternative SCMs in Arizona, possible test methods for fly ash alternatives, and testing considerations for alternative cementitious systems, including desired performance criteria. The survey revealed the most commonly used SCMs nationwide are silica fume, Class C fly ash, and slag cement. A third of survey respondents reported that supplies are consistent, reliable, and available throughout the state, with the top project selection factors of performance (68 percent of respondents) and availability (50 percent). Based on the study findings, the authors recommend (1) development of a roadmap for performance testing and life cycle assessment of fly ash alternatives for ADOT concretes, based on initial evaluation of candidate materials using computation platforms; (2) development of a ranking matrix of locally obtained candidates for the replacement of fly ash; a concept with metrics and a rating scale is presented; and (3) development of an implementation plan for using fly ash alternatives, stressing the need for additional considerations (market penetration and technical and financial barriers) and the importance of stakeholder partnerships.
• Format:
  PDF
• Funding:
  MPD0089-22
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:7eee6665fcb5a69818ccffab0defaf7c265e397ab073b7b2c5afbb0bcb7850f317660f49ed7664d2b2941512de84e92056e65ecb8adf03d34ae1331a4fc9bbbf
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/86949/dot_86949_DS1.pdf
• File Type:
  [PDF - 2.66 MB ]