Investigation of Portland Cement Concrete Mix Consistency and Concrete Performance Using Two-Stage Mixing Process

The objective of this study was to investigate the effects of different mixing processes, particularly a two-stage mixing process, on fresh and hardened characteristics of pastes and concrete. Characteristics studied for pastes included rheological effects (i.e., yield stress, thixotropy, viscosity, and peak stress) and compressive strength for mixes prepared in a Hobart mixer and a high-shear mixer. Parameters measured for the concrete study included fresh concrete air and slump, compressive strength, and hardened concrete air void characteristics. The paste study results show that for increased mixing time, the compressive strength is not significantly influenced. The rheology results show that longer mixing times with a high-shear mixer lead to lower viscosity, thixotropy, and peak stress; this indicates better-mixed slurry when compared with a shorter mixing time and the Hobart mixer. The fresh concrete made with the two-stage mixing process shows reduction in air content, and the hardened concrete shows little change in compressive strength when compared with the concrete produced with the one-step mixing process. Rapid air void analysis results indicate that the two-stage mixing method may be beneficial for mixes containing portland cement as a sole binder in freeze–thaw durability.

• Record URL:
  • https://doi.org/10.3141/1979-04
• 
• Summary URL:
  • http://scholar.google.com/scholar_lookup?title=Investigation+of+Portland+Cement+Concrete+Mix+Consistency+and+Concrete+Performance+Using+Two-Stage+Mixing+Process&author=T.+Rupnow&author=V.+Schaefer&author=K.+Wang&author=B.+Hermanson&publication_year=2006
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0309099897
• Authors:
  • Rupnow, Tyson D
  • Schaefer, Vernon R
  • Wang, Kejin
  • Hermanson, Benjamin L
• Publication Date: 2006

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 12-20
• Monograph Title: Concrete Materials 2006
• Serial:
  • Transportation Research Record: Journal of the Transportation Research Board
  • Issue Number: 1979
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Air content; Air voids; Binders; Cement paste; Compressive strength; Concrete mixing; Consistency; Freeze thaw durability; Fresh concrete; Mixers; Mixtures; Performance; Portland cement concrete; Rheology; Slurry; Thixotropy; Time; Viscosity; Yield stress
• Uncontrolled Terms: Hardened concrete; Peak stress; Slump; Two-stage concrete mixing
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 01024704
• Record Type: Publication
• ISBN: 0309099897
• Files: TRIS, TRB
• Created Date: May 25 2006 7:57AM