A STUDY OF SOME FACTORS INFLUENCING THE WEATHERING OF PAVING ASPHALTS

THREE ASPHALTIC MATERIALS OF DIFFERENT WEATHERING RESISTANT CHARACTERISTICS WERE USED TO STUDY THE INFLUENCE OF VARIATIONS IN WEATHERING CONDITIONS ON SELECTED ASPHALT PROPERTIES. VARIATIONS IN WEATHERING INCLUDED (1) HEATING IN THE ABSENCE OF LIGHT, (2) HEATING WITH THE PRESENCE OF INFRARED RADIATION AND (3) HEATING WITH THE PRESENCE OF ULTRA-VIOLET RADIATION. THE EFFECTS OF WEATHERING WERE DETERMINED BY MEASURING THE CHANGES IN PENETRATION, SOFTENING POINT, AND DUCTILITY OF THE ASPHALT RESIDUES AFTER VARIOUS EXPOSURE PERIODS WITH THE THIN-FILM OVEN TEST, AND INFRARED AND ULTRA-VIOLET RADIATION. THE USE OF THE ROTATING INCLINED SHELF PRINCIPLE APPEARS TO DEVELOP FILM THICKNESSES MORE NEARLY REPRESENTATIVE OF THOSE EXISTING IN PAVING MIXTURES AND TO PRODUCE MORE UNIFORM WEATHERING OF THE ASPHALT SAMPLE WITH A SUFFICIENT AMOUNT OF ASPHALT TO PREPARE A SPECIMEN FOR THE STANDARD PENETRATION TEST. WEATHERING IN THE ABSENCE OF LIGHT AT 225 F. CAUSED A DECREASE IN PENETRATION, AND INCREASE IN SOFTENING POINT TEMPERATURE OF THE ASPHALTS WITH TIME. WEATHERING IN THE PRESENCE OF ULTRAVIOLET RADIATION CAUSED SUBSTANTIAL REDUCTIONS IN PENETRATION OF ASPHALTS USED, INCREASE IN THEIR SOFTENING POINT TEMPERATURES, BUT CAUSED EITHER AN INCREASE OR DECREASE IN DUCTILITY DEPENDING UPON THE ASPHALT. WEATHERING IN THE PRESENCE OF INFRARED RADIATION CAUSED REDUCTION IN PENETRATION AND INCREASE IN SOFTENING POINT TEMPERATURES, THE CHANGES BEING INTERMEDIATE BETWEEN THOSE FOR WEATHERING IN THE PRESENCE OF ULTRAVIOLET RADIATION AND IN THE ABSENCE OF LIGHT.

• Supplemental Notes:
  • Vol 26, P 126
• Authors:
  • Vallerga, B A
  • Monismith, C L
  • Granthem, K
• Conference:
  • Assoc Asphalt Paving Technol Proc
• Publication Date: 1957

Subject/Index Terms

• TRT Terms: Asphalt; Bituminous mixtures; Ductility; Films (Coatings); Heating (Structures); Infrared radiation; Measurement; Oven tests; Pendulum tests; Softening point; Temperature; Thickness; Thin films; Ultraviolet radiation; Waste products (Materials); Weathering
• Uncontrolled Terms: Change; Film thickness; Thin film oven test
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00210951
• Record Type: Publication
• Source Agency: Highway Research Board Bibliography
• Files: TRIS
• Created Date: Jun 3 1994 12:00AM