STRIPPING IN ASPHALTIC CONCRETE MIXES: OBSERVATIONS AND TEST PROCEDURES

TWO TESTS ARE DEVELOPED FOR THE EVALUATION OF THE STRIPPING RESISTANCE OF HOT MIX ASPHALTIC CONCRETE. THE MODIFIED STATIC IMMERSION TEST UTILIZES COARSE AGGREGATE AND CAN BE USED IN SELECTING THE MOST SUITABLE ASPHALT SOURCE AND TYPE OF ANTI-STRIPPING ADDITIVE FOR THE AGGREGATE UNDER TEST. THE IMMERSION-MARSHALL TEST UTILIZES THE ACTUAL ASPHALTIC CONCRETE MIX DESIGNED FOR THE PAVEMENT AND IS USED IN DETERMINING THE MOST SUITABLE CONCENTRATION OF ANTI- STRIPPING ADDITIVE. CRITERIA USED IN BOTH TEST METHODS ARE BASED ON VISUAL APPRAISALS OF THE AMOUNT OF STRIPPING. A CRITERION BASED ON THE PERFORMANCE OF THE ASPHALT/AGGREGATE COMBINATION IS PROPOSED FOR THE PERCENT RETAINED STABILITY OF THE SAME MIX CONTAINING ADDITIVES. THREE BASIC TYPES OF ANTI-STRIPPING ADDITIVES WERE USED IN A SERIES OF TESTS WITH CARBONATE AND NON-CARBONATE AGGREGATES. THE HEAT STABILITY OF THESE ADDITIVES IS DESCRIBED AS GOOD, INTERMEDIATE AND POOR. ENCOURAGING RESULTS ARE OBTAINED WITH BOTH TYPES OF AGGREGATES, NON-CARBONATES GENERALLY BENEFITING MORE. HYDRATED LIME IS FOUND TO BE AN EXCELLENT ANTI-STRIPPING ADDITIVE WHEN USED WITH NON-CARBONATE AGGREGATES. THE MOVEMENT OF WATER WITHIN AN ASPHALTIC MIX IS DISCUSSED AND AN EXPERIMENT DESCRIBED WHICH PROVIDES CLUES TO THE MANNER IN WHICH THIS MOVEMENT OCCURS. PHOTOGRAPHS SHOW THE STRIPPING BEHAVIOUR OF ASPHALT FILMS ON COARSE AGGREGATE, AND REVEAL THE TENSILE FORCES CREATED IN THE ASPHALT AT AIR/ WATER/ASPHALT JUNCTIONS. SOME SUGGESTIONS ARE MADE WHICH ACCOUNT FOR THE OBSERVED PROGRESSION OF STRIPPING INTO THE PAVEMENT. /CGRA/

• Supplemental Notes:
  • Vol12, pp 61-88, 1 FIG, 12 TAB, 6 PHO, 11 REF, 3 APP
• Authors:
  • Field, F
  • Phang, W A
• Publication Date: 1967-11

Media Info

• Serial:
  • Canadian Technical Asphalt Association, Proceeding
  • Publisher: POLYSCIENCE PUBLICATIONS INC.

Subject/Index Terms

• TRT Terms: Additives; Aggregates; Air water interfaces; Asphalt; Asphalt concrete; Bituminous mixtures; Calcium hydroxide; Carbonates; Coarse aggregates; Evaluation; Hot mix asphalt; Marshall test; Motion; Stripping (Pavements); Tension; Test procedures; Testing; Water
• Uncontrolled Terms: Immersion; Tensile stress
• Old TRIS Terms: Marshall stability marshall stability & flow test flow
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00210576
• Record Type: Publication
• Source Agency: CANADIAN GOOD ROADS ASSOCIATION
• Files: TRIS
• Created Date: Aug 17 1994 12:00AM