Design and evaluation of high-volume fly ash (HVFA) concrete mixes, report A : evaluation of HVFA cementitious paste and concrete mixtures.

Details

• Corporate Creators:
  Missouri University of Science and Technology
• Subject/TRT Terms:
  Cement Additives Concrete Construction Economic Impacts Fly Ash Mix Design Pavements--Performance Performance Tests Portland Cement Portland Cement--Additives Recycled Materials Reinforced Concrete Reinforced Concrete--Testing

  More +
• Publication/ Report Number:
  TRyy1110
• Resource Type:
  Tech Report
• Geographical Coverage:
  Missouri
• Corporate Publisher:
  Missouri. Department of Transportation
• Abstract:
  In the Paste Screening Study, 25 combinations of five Type I/II portland cements
  
  and five Class C fly ashes commonly used in Missouri were tested in paste form with no
  
  chemical or powder additives. Testing procedures included semi-adiabatic calorimetry,
  
  Vicat setting time, miniature slump, and compressive strength at one and 28 days. The
  
  two most reactive and two least reactive combinations (defined by one day strengths)
  
  were further evaluated in the Paste Main Effects Study. Eighty mixtures were examined.
  
  In the Paste Main Effects Study, the effects of two levels each of WR/HRWR,
  
  gypsum, calcium hydroxide (lime), rapid set cement (RSC), and gypsum-lime, and
  
  gypsum-RSC were determined. Except for the WR/HRWR dosage level experiment, all
  
  other mixtures contained a low WR/HRWR dosage. Except for the gypsum level
  
  experiment, all other mixtures contained 4% gypsum. The lime levels were 5 and 10%
  
  and the RSC levels were 10 and 20%. All percentages are by mass of fly ash. Sixty-four
  
  mixtures were examined.
  
  The objective of the Concrete Properties Study was to scale up from paste to
  
  concrete the most promising powder additive combinations and then evaluate the
  
  mixtures in terms of plastic and hardened properties. Thus the mixture matrix included
  
  ordinary portland cement (OPC)-fly ash blends at two levels (same as in the Paste Main
  
  Effects Study) and fly ash at three levels (zero, 50 and 70%). WR dosage (nominal
  
  dosage), gypsum content (4%), lime content (10%), and RSC content (20%) were held
  
  constant. Ten concrete mixtures were evaluated.
  
  At the 50% fly ash level, one day strengths were low no matter which powder
  
  additives was used, but good strengths were achieved by day 3. At the 70% fly ash level, the concrete was weaker than at zero and 50% fly ash, but reasonable strengths were
  
  reached at 28 days. At 50% fly ash, abrasion resistance was somewhat lower. At 70% the
  
  effect was much worse. In regard to drying shrinkage, it appears that HVFA mixtures
  
  shrink less than their OPC counterparts. In a comparison to OPC mixtures, rapid chloride
  
  permeability (RCP) was lower for 50% fly ash mixtures, but 70% fly ash mixtures are
  
  more permeable. All HVFA mixtures had greater freeze-thaw Durability Factors than the
  
  OPC mixtures, and were at 93 or above. However, all fly ash mixtures did poorly in
  
  regard to salt scaling. Reaction time (calorimeter curve time, setting time, stiffening time)
  
  varied as a function of characteristics of the OPC and fly ash in conjunction with each
  
  other, type and level of powder additives used, dosage of WR/HRWR, and the type of
  
  test method used for evaluation.
  
  
• Format:
  PDF
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:20e663b5b86f6667e303c4650dd1f63d6f948026e82c3bd62a689305128ac683
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/25526/dot_25526_DS1.pdf
• File Type:
  [PDF - 5.53 MB ]