FINISHABILITY OF GAP-GRADED VS. CONTINOUSLY-GRADED CONCRETE--TECH REPORT NO 8

THE TESTS WERE CONDUCTED ON SLABS, 3-FT. SQUARE AND 6-IN. THICK, CAST IN STEEL-FRAMED MOLDS WITH 12 DIFFERENT MIXES OF GAP- AND CONTINOUSLY-GRADED CONCRETES. THE PROCEDURE AFTER BRINK WAS USED TO CONSOLIDATE AND FINISH THE CONCRETE. OBSERVATIONS WERE MADE ON THE PHYSICAL APPEARANCE OF THE PLASTIC CONCRETE. PICTORIAL RECORDS OF THE FINISHED SURFACES ARE PRESENTED. THE RECORDED VIBRATION TIME THE NUMBER OF STRIKE-OFFS NEEDED TO OBTAIN A GOOD SURFACE FINISH, AND THE PICTORIAL RECORDS OF THE FINAL APPEARANCE ALL CLEARLY SHOW THAT, FOR EQUAL COMPRESSIVE STRENGTH, DEPSITE ITS LESS CEMENT CONTENT AND HIGHER AGGREGATE-CEMENT RATIO, GAP-GRADED CONCRETE IS EQUALLY PLACEABLE, WORKABLE, AND FINISHABLE AS ITS CONTINUOUSLY- GRADED COUNTERPART. IT IS CONCLUDED THAT GAP-GRADED CONCRETE, THOUGH WITH A RELATIVELY STIFFER AND DRIER MIX, COULD BE PLACED AND FINISHED, WITHOUT UNDUE EFFORT FOR ALL HIGHWAY FACILITIES WHEREIN CONTINUOUSLY-GRADED CONCRETE HAS BEEN USED. A CONSIDERABLE SAVING IN CEMENT CONTENT AND APPRECIABLE IMPROVEMENTS IN PHYSICAL AND MECHANICAL PROPERTIES ARE THE REALISTICALLY ACHIEVABLE ADVANTAGES THROUGH THE USE OF GAP-GRADED CONCRETE. /AUTHOR/

  • Corporate Authors:

    South Dakota School of Mines and Technology, Rapid City

    501 East St Joseph Street
    Rapid City, SD  United States  57701

    South Dakota Department of Transportation

    700 East Broadway Avenue
    Pierre, SD  United States  57501

    Bureau of Public Roads /US

    400 7th Street, SW
    Washington, DC  United States  20590
  • Authors:
    • Li, S T
    • Ramakrishnan, V
  • Publication Date: 1970-5

Subject/Index Terms

Filing Info

  • Accession Number: 00212084
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Report/Paper Numbers: 642 (68)
  • Files: TRIS, STATEDOT
  • Created Date: Sep 28 1970 12:00AM