MOISTURE IN HOT-MIX BITUMINOUS PAVEMENTS

THE NATIONAL ASPHALT PAVEMENT ASSOCIATION IS INTERESTED IN DETERMINING A TRULY ALLOWABLE MOISTURE CONTENT FOR HOT-MIX BITUMINOUS PAVEMENTS PRIMARILY FROM THE ECONOMIC STANDPOINT BUT ALSO FROM THE STANDPOINT THAT A LITTLE MOISTURE DURING THE MIXING CYCLE MAY BE BENEFICIAL. THE FIRST STEP IN NAPA'S STUDY OF "ALLOWABLE MOISTURE IN HOT-MIX BITUMINOUS PAVING MIXTURES" IS BASED ON THE POSTULATION THAT SIGNIFICANT AMOUNTS OF MOISTURE CONTENT IS UNECONOMICAL PROVIDED ADEQUATE COATING CAN BE OBTAINED AT THIS LEVEL IS BENEFICIAL TO THE MIX, IT SHOULD NOT BE REMOVED. THE STUDIES REPORTED HEREIN WERE MADE TO PROVIDE AN INDICATION OF THE LEVEL OF MOISTURE CONTENT IN PAVEMENTS THROUGHOUT THE UNITED STATES. THESE STUDIES SHOW THAT SIGNIFICANT AMOUNTS OF MOISTURE EXIST IN PAVEMENTS SHOWING SATISFACTORY SERVICE. MEDIAN MOISTURE CONTENTS WERE 0.34 PER CENT FOR SURFACE COURSES AND 0.35 PER CENT FOR BINDER COURSES. THE MOISTURE CONTENT OF THE BINDER COURSE VARIED WITH, AND WAS GENERALLY HIGHER THAN, THE MOISTURE CONTENT IN THE SURFACE COURSE. MOISTURE CONTENT SHOWED NO CORRELATION WITH PER CENT VOIDS OR WITH AGE PAST THE FIRST YEAR. THERE WAS GENERAL TREND FOR MIOSTURE CONTENT TO VARY WITH RAINFALL WHEN AGGREGATE TYPE WAS CONSIDERED. THERE APPEARED TO BE TRENDS FOR MOISTURE CONTENT TO VARY WITH THE TYPE OF AGGREGATE IN THE MIX AND THE TYPE OF UNDERLYING BASE COURSE. MOISTURE CONTENTS WERE LOWEST FOR MIXES CONTAINING DENSE NON-POROUS AGGREGATES, AND HIGHEST FOR MIXES CONTAINING POROUS AGGREGATES. ALSO, MOISTURE CONTENTS WERE LOWEST WHERE MIXES WERE PLACED ON TREATED BASES OR PORTLAND CEMENT AND HIGHEST ON FLEXIBLE BASES. /NAPA/

  • Supplemental Notes:
    • Publication QIP 37, 12 PP.
  • Corporate Authors:

    National Asphalt Pavement Association

    5100 Forbes Boulevard
    Lanham, MD  USA  20706-4407
  • Authors:
    • Foster, C R
  • Publication Date: 1961-7

Subject/Index Terms

Filing Info

  • Accession Number: 00210894
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Apr 20 1970 12:00AM