00211681

Component

http://onlinepubs.trb.org...s/hrr/1971/350/350-001.pdf

A COMPREHENSIVE RESEARCH PROGRAMS HAS BEEN CONDUCTED TO DEVELOP FUNDAMENTAL METHODS FOR MEASURING THE CONSISTENCY OF ASPHALTIC MATERIALS AND TO STUDY THE FLOW PROPERTIES OF ASPHALT CEMENTS OVER THE RANGE IN TEMPERATURES ENCOUNTERED IN CONSTRUCTION AND SERVICE IN PAVEMENTS. CONCURRENTLY, A NUMBER OF SPECIFICATIONS USING REQUIREMENTS BASED ON THE NEW FUNDAMENTAL METHODS HAVE BEEN PROPOSED OR USED AS THE BASIS FOR PURCHASING ASPHALT. IN AN ATTEMPT TO GIVE SOME GUIDANCE AND STANDARDIZATION TO THESE SPECIFICATIONS, THE COMMITTEE ON MATERIALS OF THE AMERICAN ASSOCIATION OF STATE HIGHWAY OFFICIALS (AASHO) UNDERTOOK THE DEVELOPMENT OF SPECIFICATIONS BASED ON VISCOSITY GRADING AT 140 F. FOUR GRADES WERE SELECTED, AND LIMITING REQUIREMENTS WERE ADDED FOR VISCOSITY AT 275 F. BECAUSE LOW- TEMPERATURE VISCOSITY TESTS WERE NOT PERFECTED FOR NATIONAL USE, LIMITING REQUIREMENTS USING THE PENETRATION TEST AT 77 F WERE SELECTED. OTHER REQUIREMENTS INCLUDED MAXIMUM VISCOSITY AND MINIMUM DUCTILITY LIMITS ON THE RESIDUE FROM THE THIN-FILM OVEN TEST. CONVENTIONAL SOLUBILITY, FLASH POINT, AND OLIENSIS SPOT TEST REQUIREMENTS ALSO WERE INCLUDED IN THE SPECIFICATION. THE LIMITS FOR THE REQUIREMENTS OF THE 4 GRADES WERE SET BY A SYSTEMATIC STUDY OF TEST CHARACTERISTICS OF ASPHALT CEMENTS PRODUCED IN THE UNITED STATES. THE SPECIFICATION HAS BEEN ADOPTED BY AASHO, DESIGNATED AS SPECIFICATION M 226, AND PUBLISHED AS AN ALTERNATE TO SPECIFICATION M 20, WHICH IS BASED ON PENETRATION GRADING AND REMAINS IN EFFECT. THE ADVANTAGES OF SPECIFICATION M 226 ARE THAT IT PROVIDES INFORMATION ON THE KIND OF ASPHALT BEING USED AND A MEANS FOR SELECTING THE ASPHALT THAT SHOULD RESULT IN IMPROVED MIXTURE DESIGN AND MORE UNIFORM CONSTRUCTION PRACTICES. THIS SHOULD, IN TIME, LEAD TO IMPROVED PAVEMENT PERFORMANCE. /AUTHOR/

Sponsored by Committee on Characteristics of Bituminous Materials and presented at the 50th Annual Meeting. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.

01410282

Krchma, L C

pp 1-14

1971

Highway Research Record

50th Annual Meeting of the Highway Research Board

0309019621

Digital/other

Figures (9) ; References (8) ; Tables (1)

Asphalt; Asphalt cement; Atterberg limits; Bituminous materials; Bituminous mixtures; Classification; Ductility; Flash point; Grading (Earthwork); Mix design; Oven tests; Research; Soil penetration test; Specifications; Temperature; Thin films; Viscosity

Grading; Thin film oven test

Highways; Materials; Research

TRIS, TRB

Oct 3 1971 12:00AM

• GENERAL DISCUSSION OF VISCOSITY GRADING OF ASPHALTS
• PAVING ASPHALT PROPERTIES
• SOME ALBERTA EXPERIENCE WITH PENETRATION - GRADED ASPHALT CEMENTS HAVING DIFFERING VISCOSITYIES AT 140 F
• TEMPERATURE-SUSCEPTIBILITY CONTROL IN ASPHALT-CEMENT SPECIFICATIONS
• VISCOSITY GRADING FOR ASPHALT CEMENTS