RHEOLOGIC BEHAVIOR OF ASPHALT CONCRETE

AN ATTEMPT WAS MADE TO ASSESS THE USEFULNESS OF VISCOELASTIC ANALYSIS AS APPLIED TO THE BEHAVIOR OF ASPHALT CONCRETE AND TO THE BEHAVIOR OF STRUCTURAL SYSTEMS OF WHICH THIS MATERIAL IS A COMPONENT. THE ANALYSIS OF MATHEMATICAL RELATIONS AND SIMPLE MODELS INDICATES THAT THEY HAVE LIMITED APPLICABILITY IN PREDICTING THE REAL BEHAVIOR OF ASPHALT CONCRETE FOR ENGINEERING USE. STUDIES OF THE MORE GENERALIZED REPRESENTATIONS THROUGH CREEP, RELAXATION, CONSTANT RATE-OF-STRAIN, DYNAMIC, AND FLEXURAL STIFFNESS TESTS APPEAR TO GIVE A REASONABLE REPRESENTATION OF THE INFLUENCE OF TIME OF LOADING AND TEMPERATURE ON THE STRESS- STRAIN CHARACTERISTICS OF ASPHALT CONCRETE. THE DATA SUGGEST THAT ASPHALT CONCRETE CAN BE CONSIDERED TO BE A LINEAR VISCOELASTIC MATERIAL SO LONG AS DEFORMATIONS ARE SMALL. WITHIN THIS RANGE, THE MATERIAL CAN BE CONSIDERED TO BE THERMORHEOLOGICALLY SIMPLE. THUS, THE PRINCIPLE OF TIME- TEMPERATURE SUPERPOSITION APPEARS TO BE APPLICABLE. THE CREEP TEST APPEARS TO BE MOST APPROPRIATE BECAUSE OF SIMPLICITY IN EQUIPMENT REQUIREMENTS AND BECAUSE IT CAN BE CONDUCTED RELATIVELY EASILY OVER A RANGE IN TEMPERATURES. TO OBTAIN THE MODULUS AS A FUNCTION OF TIME AND TEMPERATURE FROM THE RESULTS OF THE CREEP TEST, USE CAN BE MADE OF A NUMERICAL APPLICATION OF THE SUPERPOSITION PRINCIPLE. MEASUREMENT OF FLEXURAL STIFFNESS SEEMS TO BE A DESIRABLE PROCEDURE BECAUSE OF POSSIBLE DIFFERENCES IN TENSILE AND COMPRESSIVE BEHAVIOR AT LONGER TIMES OF LOADING. THE APPROXIMATE PROCEDURE DEVELOPED BY VAN DER POEL CAN GIVE A REASONABLE REPRESENTATION OF STIFFNESS, BUT IT IS LIMITED TO WELL COMPACTED MIXTURES. DATA PRESENTED HEREIN ARE BASED ON THE RESULTS OF A SINGLE LOAD APPLICATION. IT IS SUGGESTED THAT THE STIFFNESS CONCEPT OF VAN DER POEL SHOULD SERVE AS A USEFUL MEANS TO INCORPORATE THE TIME AND TEMPERATURE EFFECTS WITHIN EXISTING ELASTIC SOLUTIONS TO ANALYZE: (1) THE BEHAVIOR OF LAYERED SYSTEMS UNDER MOVING WHEEL LOADS, AND (2) THE CREEP OF ASPHALT MIXTURES UNDER LOAD.

• Supplemental Notes:
  • Vol 35, pp 400-451, 46 FIG, 4 TAB, 34 REF, 1 APP
• Authors:
  • Monismith, C L
  • Alexander, R L
  • Secor, K E
• Conference:
  • Assoc Asphalt Paving Technol Proc
• Publication Date: 1966-2

Subject/Index Terms

• TRT Terms: Asphalt concrete; Bituminous mixtures; Creep; Deformation curve; Elastic analysis; Flexure; Loading and unloading; Mathematical models; Motion; Motor vehicles; Rheology; Stiffness tests; Structural analysis; Superposition (Geology); Temperature; Testing; Viscoelastic materials; Viscoelasticity
• Uncontrolled Terms: Moving vehicles
• Old TRIS Terms: Elastic analysis (Structural); Loading time; Superposition
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00210785
• Record Type: Publication
• Files: TRIS
• Created Date: May 6 1994 12:00AM