SOME GENERALIZATIONS IN THEORY AND TECHNOLOGY OF ACCELERATION OF CONCRETE HARDENING

PHYSICAL PHENOMENA OCCURRING AT ELEVATED TEMPERATURES AND MECHANICAL CHANGES WHICH INFLUENCE GREATLY THE STRUCTURE AND PROPERTIES OF CONCRETE ARE DISCUSSED. SOME IMPORTANT TECHNICAL AND COMMERCIAL PROBLEMS CONNECTED WITH FABRICATION OF REINFORCED-CONCRETE UNITS ARE ALSO INCLUDED. THE PRACTICAL APPLICATION OF ACCELERATED HARDENING OF CONCRETE FOR THE MANUFACTURE OF PRECAST REINFORCED CONCRETE PRODUCTS JUSTIFIES THIS STUDY. TO ACCELERATE THE HARDENING OF CONCRETE, HIGH-EARLY-STRENGTH CEMENTS AND CONCRETE MIXTURES OF AS LOW A CONSISTENCY AS POSSIBLE WITH LOW WATER-CEMENT RATIOS SHOULD BE USED. ADDITIONAL ACCELERATION OF CONCRETE HARDENING, DEPENDING ON QUALITIES OF CEMENTS AND CONCRETES USED AND ON DEGREE OF ACCELERATION REQUIRED FOR VARIOUS METHODS, IS ACHIEVED IN THE FOLLOWING WAYS' /1/ MECHANICALLY BY POSITIVE AGITATION WITH MIXTURE, EFFICIENT COMPACTION OF CONCRETE MIXTURES BY LOADED, REPEATED AND MULTI-FREQUENCY VIBRATION, BY VIBRATORY PRESSING OR ROLLING OF THE PRODUCTS, ETC., /2/ CHEMICALLY, BY ADDITION OF CHEMICAL ADMIXTURES ACCELERATING HARDENING PREHYDRATION OF CEMENTS, TREATMENT WITH GASES /SILICON TETRAFLUORIDE, CARBON DIOXIDE/, AND /3/ PHYSICALLY CHIEFLY BY HEAT TREATMENT /LOW AND HIGH-PRESSURE STEAM TREATMENT, ELECTRICAL CURING, CURING WITH HOT GASES, IMMERSION IN WATER AND OIL, ETC./. ECONOMIC EXPEDIENCY OF ONE OR ANOTHER METHOD OF HEAT TREATMENT CAN BE DETERMINED BY' /1/ COMPARING DESIGN CHARACTERISTICS OF SEVERAL PLANTS OF EQUAL CAPACITY USING LOW- AND HIGH-PRESSURE STEAM TREATMENT, ELECTRICAL CURING AND NATURAL CURING OF CONCRETE PRODUCTS, AND /2/ INVESTIGATING ECONOMIC INDEXES CHARACTERIZING OPERATION OF EXISTING PRECASTING PLANTS. PLANTS. TECHNICAL AND ECONOMIC STUDIES REVEAL THAT VERY OFTEN FABRICATION TECHNOLOGY ASSURING OPTIMUM QUALITIES OF CONCRETE DOES NOT MEET THE REQUIREMENTS OF ECONOMY AND EASE OF PRODUCTION THEREFORE, MANY SEEMINGLY ADVANCED TECHNOLOGICAL METHODS DO NOT FIND PRACTICAL APPLICATION.

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/sr/sr90/90-038.pdf
• Supplemental Notes:
  • Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Corporate Authors:

  Highway Research Board (HRB)

  Washington, DC   
• Authors:
  • Mironov, S A
• Publication Date: 1966

Media Info

• Media Type: Print
• Features: Figures; Photos; References;
• Pagination: pp 465-474
• Monograph Title: Symposium on structure of Portland cement paste and concrete
• Serial:
  • Highway Research Board Special Report
  • Issue Number: 90
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Accelerating agents; Chemical substances; Concrete; Concrete hardening; Consistency; Economic analysis; Fabrication; Hardness; High early strength cement; Machinery; Mechanical properties; Metal heating; Physical properties; Precast concrete; Reinforced concrete; Steam curing; Temperature; Water cement ratio
• Uncontrolled Terms: Change; Concrete properties; Heat treatment
• Old TRIS Terms: Accelerating (Process); Chemical means; Concrete consistency; Mechanical equipment
• Subject Areas: Economics; Highways; Materials;

Filing Info

• Accession Number: 00212459
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Nov 18 1994 12:00AM