DETERMINATION OF AIR CONTENT IN HARDENED CONCRETE BY GAMMA- RAY TRANSMISSION

AN INVESTIGATION WAS CONDUCTED OF A METHOD OF DETERMINING AIR CONTENT OF HARDENED CONCRETE BY GAMMA-RAY TRANSMISSION. THE STUDY WAS BASED ON THE PREMISE THAT SINCE GAMMA RAY TRANSMISSION WAS RELATED TO DENSITY, IT COULD ALSO BE RELATED TO CONCRETE AIR CONTENT, DEPENDING ON THE CORRELATION BETWEEN AIR CONTENT AND DENSITY. A DIRECT STATISTICAL COMPARISON WAS ATTEMPTED BETWEEN AIR CONTENT AS MEASURED BY THE LINEAR TRAVERSE METHOD AND BY GAMMA-RAY TRANSMISSION. A SEALED SOURCE OF RADIUM 226, A SCINTILLATION DETECTOR, AND APPROPRIATE SCALER WERE USED TO MEASURE CYLINDRICAL SAMPLES OF HARDENED CONCRETE OF VARYING LENGTHS MADE WITH THREE KINDS OF COARSE AGGREGATE. THE THEORETICAL ASSUMPTIONS PROVED TO BE INCOMPATIBLE WITH THE EXPERIMENTAL TECHNIQUES. THE ANALYSIS OF ERROR COMPONENTS, PERFORMED SUBSEQUENT TO THIS STUDY, INVESTIGATED AND DEFINED THE EFFECTS ON CONCRETE DENSITY OF VARIABLES OTHER THAN AIR CONTENT. THIS STUDY CONCLUDES THAT THERE ARE CERTAIN INHERENT LIMITATIONS IN THE NUCLEAR METHOD FOR MEASURING AIR CONTENT OF HARDENED CONCRETE WHICH CANNOT BE ELIMINATED BY FURTHER RESEARCH OR ADDITIONAL INSTRUMENTAL DEVELOPMENT. /AUTHOR/

  • Supplemental Notes:
    • Research RePORT NO R-490 27 PP
  • Corporate Authors:

    Michigan Department of State Highways

    State Highways Building, PO Drawer K
    Lansing, MI  United States  48904
  • Publication Date: 1967-9

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Filing Info

  • Accession Number: 00212537
  • Record Type: Publication
  • Files: TRIS, STATEDOT
  • Created Date: Jan 24 1994 12:00AM