THE FUNCTION OF WATER IN HARDENING CONCRETE

IT IS ASSUMED THAT, IN AN IDEAL CEMENT COMPOSED ONLY OF THE CALCIUM SILICATES, THE CEMENT HYDRATES AS CIRCUMSTANTIAL EVIDENCE INDICATES IT MIGHT. AFTER THE CEMENT HAS HYDRATED FOR A WEEK OR MORE THE TEMPORARY WATER VOIDS HAVE BEEN FILLED WITH HYDRATION PRODUCTS WHICH APPARENTLY HAVE COME FROM THE OUTER SURFACES OF THE CEMENT GRAINS. THE WATER HAS TRANSFORMED THE CALCIUM SILICATE INTO CRYSTALLINE HYDRATED LIME AND A NONCRYSTALLINE SUBSTANCE, GEL, THE CEMENTING AGENT WHICH SOLIDIFIES THE MASS BY GROWING INTO THE VOID SPACES WITH THE ADVENT OF WATER. WATER IS NOT NECESSARY FOR THE CONTINUED EXISTENCE OF THE GEL. ULTIMATE STRENGTH IS REDUCED BY DRYING BECAUSE OF THE DESTRUCTIVE INTERNAL STRESSES CAUSED BY GEL TENDING TO SHRINK WHEN OTHER CONSTITUENTS DO NOT. THE WATER NEEDED FOR CHEMICAL COMBINATIONS IS ABOUT 10% OF THE WEIGHT OF THE CEMENT, BUT FOR THE PRODUCTION OF GEL AT LEAST 3 TIMES AS MUCH IS NEEDED. /AUTHOR/

• Record URL:
  https://onlinepubs.trb.org/Onlinepubs/hrbproceedings/16/16-017.pdf
• Supplemental Notes:
  • Vol 16, pp 216-219, 3 REF. 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:
  • CARLSON, R W
• Publication Date: 1937

Media Info

• Media Type: Digital/other
• Monograph Title: Proceedings of the Sixteenth Annual Meeting of the Highway Research Board Held at Washington, D.C. November 18-20, 1936
• Serial:
  • Highway Research Board Proceedings
  • Volume: 16
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Bonding; Calcium; Cement; Concrete; Concrete hardening; Gels; Hardness; Silicates; Void ratios; Water
• Old TRIS Terms: Calcium silicate gel; Cementing agents; Void
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00213786
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Aug 8 1971 12:00AM