USE OF MICROWAVE OVEN FOR RAPID DRYING OF AGGREGATE SAMPLES

PRELIMINARY TESTS CONDUCTED IN LATE 1965 AND EARLY 1966 INDICATED A MICROWAVE OVEN COULD BE A USEFUL TOOL IN THE PERFORMANCE OF QUALITY CONTROL TESTING. THE PURPOSE OF THIS STUDY WAS TO COMPARE THE CHARACTERISTICS OF MICROWAVE DRYING WITH CONVENTIONAL DRYING. THE REPORT EVALUATES THE RAPID DRYING CHARACTERISTICS OF MICROWAVE HEATING AND ITS APPLICATION TO HIGHWAY MATERIALS TESTING. MICROWAVE HEATING IS THE FASTEST KNOWN WAY TO HEAT WITH THE LEAST AMOUNT OF POWER IN THE SMALLEST AMOUNT OF SPACE. MICROWAVES ARE SHORT ELECTRO-MAGNETIC WAVES OF THE SAME KIND PRESENTLY USED IN RADAR, TELEVISION, AND RADIO. THE HEART OF THE LITTON MICROWAVE OVEN IS A 1000 WATT CONTINUOUS WAVE MAGNETRON OPERATING AT A FREQUENCY OF 2450 MEGACYCLES. ORIGINALLY THE UNIT WAS DESIGNED FOR FOOD PREPARATION; SUBSEQUENT MODIFICATIONS HAVE MADE IT APPLICABLE TO LABORATORY USE. THE AGGREGATE AND SOILS STUDIES INDICATE THE UNIT CAN BE USED FOR CONTROL TESTING WITH CONSIDERABLE TIME SAVING ADVANTAGE. IT IS APPROXIMATELY 10 TIMES FASTER THAN CONVENTIONAL OVENS. THE CONCRETE STUDY SHOWED GOOD POSSIBILITIES FOR DETERMINING THE MOISTURE CONTENT OF FRESHLY MIXED PORTLAND CEMENT CONCRETE. /AUTHOR/

• Supplemental Notes:
  • 1474, 10
• Corporate Authors:

  Colorado Department of Highways

  4201 East Arkansas Avenue
  Denver, CO  United States  80222

  Bureau of Public Roads /US

  400 7th Street, SW
  Washington, DC  United States  20590
• Publication Date: 0

Subject/Index Terms

• TRT Terms: Aggregates; Drying; Materials tests; Microwaves; Moisture content; Ovens; Polymer concrete; Portland cement concrete; Quality control; Soil tests
• Uncontrolled Terms: Aggregate testing
• Old TRIS Terms: Quality control testing
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00215921
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Files: TRIS, STATEDOT
• Created Date: Jul 14 1970 12:00AM