Innovative Testing Protocol for Evaluation of Binder-Reclaimed Aggregate Bond Strength

The durability of asphalt mixtures is strongly related to the adhesion properties developed at the interface between binder and aggregates. The loss of adhesion implies a rapid deterioration (e.g., stripping or raveling) of pavement layers under traffic loads, especially when the pavement is affected by the presence of moisture. Adhesion is a complex phenomenon related to the mineralogical and morphological nature of aggregates as well as to the chemical binder composition and the environmental conditions. The evaluation of adhesion has become even more complicated as an increasing percentage of reclaimed asphalt pavement (RAP) is used in the production of new asphalt mixes. Therefore, adhesion properties are also related to the mechanisms developed at the interface between virgin binder and aged binder that coats the RAP aggregate surface. An innovative procedure to evaluate the compatibility of the system virgin binder–RAP aggregate was proposed in this study. This procedure allowed the substrate of a RAP aggregate to be simulated in the laboratory and could integrate the binder bond strength test currently used to investigate bonding properties and water sensitivity of the system binder and virgin aggregates. Tests were performed with various aggregate sources, several modified binders, and two conditioning types (dry and wet). It was found that the procedure was able to discriminate different test configurations and variables. In particular, the artificial reclaimed aggregate substrate ensured higher adhesion performance compared with the virgin aggregate, especially in the wet condition, regardless of the modification level of the virgin bitumen.

[1]  Dallas N. Little,et al.  CHEMICAL AND MECHANICAL PROCESSES OF MOISTURE DAMAGE IN HOT-MIX ASPHALT PAVEMENTS , 2003 .

[2]  Jo Sias Daniel,et al.  Mechanistic and Volumetric Properties of Asphalt Mixtures with Recycled Asphalt Pavement , 2005 .

[3]  S. Commuri,et al.  A Laboratory Investigation into the Effect of Long-Term Oven Aging on RAP Mixes Using Dynamic Modulus Test , 2012 .

[4]  Robert L. Lytton,et al.  Limits on Adhesive Bond Energy for Improved Resistance of Hot-Mix Asphalt to Moisture Damage , 2006 .

[5]  Mustapha Kaci,et al.  Influence of thermo-oxidative aging on chemical composition and physical properties of polymer modified bitumens , 2012 .

[6]  Hussain U Bahia,et al.  Adhesive and Cohesive Properties of Asphalt-Aggregate Systems Subjected to Moisture Damage , 2010 .

[7]  F L Roberts,et al.  Stripping in HMA Mixtures: State-of-the-Art and Critical Review of Test Methods , 1988 .

[8]  J D'angelo,et al.  MATERIAL PRODUCTION, MIX DESIGN, AND PAVEMENT DESIGN EFFECTS ON MOISTURE DAMAGE , 2003 .

[9]  Arthur R. Tarrer,et al.  EFFECT OF AGGREGATE PROPERTIES ON STRIPPING , 1988 .

[10]  Hussain U Bahia,et al.  Relating Adhesion and Cohesion of Asphalts to the Effect of Moisture on Laboratory Performance of Asphalt Mixtures , 2005 .

[11]  László Gáspár,et al.  Synthesis of European knowledge on asphalt recycling: options, best practices and research needs , 2012 .

[12]  Ulf Isacsson,et al.  Testing and appraisal of polymer modified road bitumens—state of the art , 1995 .

[13]  D. Lesueur.  The colloidal structure of bitumen: consequences on the rheology and on the mechanisms of bitumen modification. , 2009, Advances in colloid and interface science.

[14]  Audrey Copeland,et al.  Reclaimed Asphalt Pavement in Asphalt Mixtures: State of the Practice , 2011 .

[15]  Yusuf Mehta,et al.  A study to determine the degree of partial blending of reclaimed asphalt pavement (RAP) binder for high RAP hot mix asphalt , 2011 .

[16]  Rajib B. Mallick,et al.  A CRITICAL REVIEW OF VMA REQUIREMENTS IN SUPERPAVE , 1998 .

[17]  Hussain U Bahia,et al.  Measuring the Effect of Moisture on Asphalt–Aggregate Bond with the Bitumen Bond Strength Test , 2011 .

[18]  Wagh,et al.  THE EFFECT OF THE PHYSICAL AND CHEMICAL CHARACTERISTICS OF THE AGGREGATE ON BONDING , 1991 .

[19]  Burak Sengoz,et al.  Effect of asphalt film thickness on the moisture sensitivity characteristics of hot-mix asphalt , 2007 .

[20]  Serji N. Amirkhanian,et al.  Laboratory investigation of moisture damage in rubberised asphalt mixtures containing reclaimed asphalt pavement , 2009 .

[21]  J. C. Petersen,et al.  CHEMISTRY OF ASPHALT-AGGREGATE INTERACTION: RELATIONSHIP WITH PAVEMENT MOISTURE-DAMAGE PREDICTION TEST , 1982 .

[22]  R. Landel,et al.  The Temperature Dependence of Relaxation Mechanisms in Amorphous Polymers and Other Glass-Forming Liquids , 1955 .

[23]  Hussain U Bahia,et al.  Role of adhesion and thin film tackiness of asphalt binders in moisture damage of HMA , 2003 .

[24]  R M Anderson,et al.  CHARACTERIZATION OF MODIFIED ASPHALT BINDERS IN SUPERPAVE MIX DESIGN , 2001 .

[25]  Gilda Ferrotti,et al.  Improved durability of recycled porous asphalt , 2013 .

[26]  Richard R. Davison,et al.  The effect of long-term oxidation on the rheological properties of polymer modified asphalts☆ , 2003 .

[27]  Audrey Copeland,et al.  Moisture Sensitivity of Modified Asphalt Binders , 2007 .

[28]  Emmanuel Chailleux,et al.  Physico-chemical analysis of five hard bitumens: Identification of chemical species and molecular organization before and after artificial aging , 2010 .

[29]  Dallas N. Little,et al.  Surface Free Energy to Identify Moisture Sensitivity of Materials for Asphalt Mixes , 2007 .