A STUDY OF CALCIUM CHLORIDE AS A STRENGTH ACCELERATOR IN PORTLAND CEMENT CONCRETE

RESULTS OF TESTS ARE PRESENTED COVERING A 25 YEAR PERIOD INVOLVING A NUMBER OF SPECIMENS UNDER VARIABLE TEST CONDITIONS. THE MOST RECENT TESTS INDICATE THAT: (1) THERE WAS A VERY DEFINITE ACCELERATION IN COMPRESSIVE STRENGTH FOR ALL CALIFORNIA CEMENTS AND FOR CONCRETE AT 1 YEAR (REGARDLESS OF THE PERCENTAGE OF CALCIUM CHLORIDE) LESS THAN WITHOUT CALCIUM CHLORIDE. (2) UNDER MOIST-ROOM INITIAL CURING AT 70 DEGREES F, THE CALCIUM CHLORIDE INCREASED THE INITIAL SHRINKAGE AS WELL AS THE SUBSEQUENT VOLUME CHANGE UNDER WETTING AND DRYING CYCLES. (3) WHEN STORED AT 100 DEGREES F AND 30 PERCENT RELATIVE HUMIDITY IMMEDIATELY AFTER FABRICATION, THE SETTING SHRINKAGE WAS LESS WITH THE CALCIUM CHLORIDE THAN WITHOUT, BUT THE SUBSEQUENT TOTAL SHRINKAGE AND WET DRY VOLUME CHANGES SUBSTANTIALLY PARALLELED THE SPECIMENS IN WHICH NO CALCIUM CHLORIDE HAD BEEN USED. (4) THE COMPRESSIVE STRENGTHS WERE NOT MATERIALLY AFFECTED BY THE INITIAL AND SUBSEQUENT CURING AND WETTING AND DRYING PROCEDURE REGARDLESS OF THE TYPE OF CEMENT OR PERCENTAGE OF CALCIUM CHLORIDE. (5) WHEN INITIALLY CURED IN THE MOIST ROOM FOR 7 DAYS, THE MODULUS OF RUPTURE AND MODULUS OF ELASTICITY DURING THE SUBSEQUENT WET-DRY CYCLES WAS AS A RULE LOWERED BY THE CALCIUM CHLORIDE, BUT THE DIFFERENTIAL WAS NOT MATERIAL EXCEPT IN THE CASE OF THE TYPE III CEMENTS. (6) WHEN INITIALLY CURED UNDER ADVERSE CONDITIONS, THE CALCIUM CHLORIDE WAS APPARENTLY BENEFICIAL WITH RELATION TO THE MODULUS OF RUPTURE AS WELL AS COMPRESSIVE STRENGTHS. (7) UNDER INITIAL THOROUGH WATER CURING CONDITIONS, CALCIUM CHLORIDE APPARENTLY INCREASES THE INITIAL SHRINKAGE AND INDUCES SUBSEQUENT GREATER WET-DRY VOLUME CHANGES, INDICATING THE SPARING USE OF THIS ADDITIVE WHEN HIGH TENSILE STRENGTH IS IMPORTANT, OR SEVERE RUSTING OF REINFORCING STEEL MAY BE FACILITATED BY THE INFILTRATION OF MOISTURE THROUGH SURFACE CRACKS. /AUTHOR/

  • Supplemental Notes:
    • No 30, pp 232-252, 21 FIG, 8 TAB, 8 REF
  • Authors:
    • STANTON, T E
  • Publication Date: 1951

Media Info

  • Monograph Title: Proceedings of the Thirtieth Annual Meeting of the Highway Research Board Held at Washington, D.C., January 9-12, 1951
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00212693
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: May 13 1994 12:00AM