AMENDMENT OF APPENDIX X2 IN ASTM C 917 EVALUATION OF CEMENT UNIFORMITY FROM A SINGLE SOURCE. TECHNICAL NOTE

American Society for Testing and Materials (ASTM) C 917 provides methods to evaluate the cement strength uniformity from a single source. Test data comparing 1976 through 1977 and 1991 reveal a general increase in strengths over that time period. In 1976, 45 percent of the laboratories had annual average 7-day strengths less than 27.6 MPa, while in 1991 none of the plants had averages below that level. The data indicate that the cement industry, overall, shipped a more consistent product in 1991 than from 1976 through 1977. The percentage of plants with a standard deviation below 2.1 MPa at 7 days increased from 63 to 81 percent during that time period. A higher percentage of plants had the total coefficient of variation and corrected deviations below 6 percent. The testing error stayed the same with the 1976 data and the 1991 data, but the testing error coefficient of variation improved.

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  • Accession Number: 00716421
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jan 31 1996 12:00AM