DETERMINATION OF WATER CONTENT OF PLASTIC CONCRETE USING A MICROWAVE OVEN

Until now there has not been a simple test that could be performed in the field to accurately determine the water content of a plastic concrete mix. Oven or hot plate drying is unsatisfactory because the heat involved hastens cement hydration which makes a portion of the water non-evaporable. In our laboratory tests, drying by microwave oven on the defrost mode has been found to essentially overcome this problem. The time interval between introduction of the mixing water and start of the test did not affect the results up to the maximum time interval tested of one hour. The accuracy of the test is such that 95% of the time the true water content can be determined to within .06 gallons/sack of cement. It takes about one hour to perform the test. Field trials on four construction projects were successfully accomplished which proved its practicality and value. (Color illustrations reproduced in black and white)

  • Supplemental Notes:
    • Prepared in cooperation with Federal Highway Administration, Bismarck, ND. North Dakota Div.
  • Corporate Authors:

    North Dakota Department of Transportation

    Materials and Research Division, 300 Airport Road
    Bismarck, ND  United States  58504-6005

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Peterson, R T
    • Leftwich, D
  • Publication Date: 1978-9

Media Info

  • Pagination: 24 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00190918
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: FHWA/ND-78/4-77B Final Rpt.
  • Files: NTIS, TRIS, USDOT, STATEDOT
  • Created Date: Mar 28 1979 12:00AM