REPORT ON USE OF ACCELERATORS IN PORTLAND CEMENT CONCRETE

THE USE IS REVIEWED OF CALCIUM CHLORIDE AND CALCIUM CHLORIDE COMPOUNDS ACCELERATORS TO ACCELERATE THE SETTING AND HARDENING OF PORTLAND CEMENT CONCRETE. THE INVESTIGATIONS REVIEWED AGREE THAT CALCIUM CHLORIDE AND OTHER SOLUABLE COMPOUNDS OF CHLORIDE BASE ACTS AS ACCELERATORS OF THE HARDENING OF CONCRETE, AND WHEN USED WITHIN LIMITS OF APPROXIMATELY 0 TO 4 PERCENT INCREASE THE STRENGTH TO A LIMITED DEGREE. THE EFFECT OF THE ACCELERATOR IS ROUGHLY IN PROPORTION TO THE AMOUNT OF ANHYDROUS CALCIUM CHLORIDE USED. SINCE THE INCREASE IN STRENGTH IS PRACTICALLY THE SAME FOR ALL AGES THE RELATIVE INCREASE IS GREATEST AT EARLY AGES. CONSIDERABLE VARIATION IN RESULTS IS SECURED WITH DIFFERENT BRANDS OF CEMENT. THE USEFUL FUNCTIONS OF SUCH ADMIXTURES APPEARED TO: (1) INCREASE THE EARLY HARDENING SO THAT THE STRUCTURE OR PAVEMENT MAY BE PUT INTO EARLIER SERVICE THAN IS POSSIBLE WITH NORMAL PORTLAND CEMENT, AND (2) COUNTERACT LOW STRENGTH DUE TO CURING CONCRETE AT LOW TEMPERATURES PROVIDED THAT THE TEMPERATURE IS NOT BELOW FREEZING, AND THE CONCRETE IS PROTECTED DURING THE SETTING PERIOD. THE RATE OF ACCELERATION FOR THE COMPOUNDS USED IS IN DIRECT RELATION TO THE CALCIUM CHLORIDE CONTENT.

• Record URL:
  https://onlinepubs.trb.org/Onlinepubs/hrbproceedings/5/5-014.pdf
• Supplemental Notes:
  • Vol 5, Pt 1, PP 132-145, 8 FIG, 5 TAB. 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.
• Authors:
  • Crum, R W
• Publication Date: 1926

Media Info

• Media Type: Digital/other
• Monograph Title: Proceedings of the Fifth Annual Meeting of the Highway Research Board Held at Washington, D.C. December 3-4, 1925. Part I: Reports of Research Committees and of Special Investigations
• Serial:
  • Highway Research Board Proceedings
  • Volume: 5
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Accelerators (Devices); Calcium chloride; Concrete curing; Concrete hardening; Hardness; Portland cement; Portland cement concrete; Temperature
• Old TRIS Terms: Accelerators
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00213727
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Nov 9 1970 12:00AM