Characterization and Performance of Zero-Cement Concrete

This study has investigated the feasibility of using five different types of class C fly ashes (FAs) sourced from Labadie, Jeffrey, Kansas City, Thomas Hill, and Sikeston power plants in the state of Missouri to synthesize zero-cement concrete (ZCC) for different structural and repair applications. Alkali activator (Alk) consisting of sodium silicate (SS), Na₂SiO₃, and sodium hydroxide (SH), NaOH were used to synthesize the ZCC. Slag, crumb rubber, and air-entraining admixture (AEA) were used in a few mixtures as additives to improve the durability of the ZCC. Approximately 300 mortar and concrete mixtures were prepared during this study to investigate the mixing procedure, water/FA, Alk/FA, SS/SH, curing regime, fresh properties, mechanical properties, durability, repair applicability, and cost analysis of the ZCC. A 5000 psi Missouri Department of Transportation (MoDOT) conventional concrete (CC) mixture was also prepared and tested for comparison purposes. This study revealed that ZCC can be used as a replacement for CC. ZCC showed good workability and adequate compressive strength for structural applications ranging from 3,660 psi to 7,465 psi based on the curing regime and source of FA. Some ZCC mixtures successfully passed 300 cycles of freeze and thaw per ASTM C666-15 procedures A and B. Furthermore, the drying shrinkage values of the ZCC specimens at all ages were significantly lower than those of the corresponding CC specimens. ZCC also presents higher corrosion resistance compared to CC. ZCC mixtures have a low to moderate permeability and chloride ion penetrability, while the CC mixture showed a high permeability and chloride ion penetrability. Finally, ZCC can be used as a repair material for existing concrete structures. The bond between ZCC as a repair material and CC as a host material was adequate and comparable to the bond between CC and CC.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Figures; Photos; References; Tables;
  • Pagination: 327p

Subject/Index Terms

Filing Info

  • Accession Number: 01689723
  • Record Type: Publication
  • Report/Paper Numbers: cmr 18-011
  • Contract Numbers: MoDOT project # TR201614
  • Files: NTL, TRIS, ATRI, USDOT, STATEDOT
  • Created Date: Dec 18 2018 8:55AM