01596182

Component

https://doi.org/10.3141/2506-07

The use of reclaimed asphalt pavement (RAP) in asphalt mix contributes to sustainable construction. However, a high percentage of RAP in asphalt mix causes concern about compromising the performance of asphalt pavement, especially cracking. The binder transfer and blending between RAP and virgin aggregate during production in an asphalt plant is a critical procedure that affects the performance of the asphalt mix. The heating of RAP by superheated virgin aggregate and the transfer of RAP binder can affect the degree to which virgin binder and RAP binder are blended and thus affect the performance of mixes containing RAP. Several parameters, such as RAP percentage, mixing time, and RAP moisture content, can affect the heating of RAP and the degree of blending between the virgin binder and RAP binder. To increase the understanding of RAP heating and RAP binder transfer, laboratory tests and numerical simulations that employed the discrete element method (DEM) were conducted for this study to investigate the temperature evolution and amount of RAP binder transfer during the mixing of superheated virgin aggregate and RAP materials in a laboratory drum mixer. The results indicated that a longer mixing time or higher superheated virgin aggregate temperature was needed for cases with a high RAP content and high RAP moisture content. The DEM simulations were found to be a promising method for studying the mixing process of superheated virgin aggregate blended with RAP materials. In the future, such DEM simulations could be applied to guide the mix production process for RAP mixes.

01596058

15-5045

English

pp 62–71

2015

Transportation Research Record: Journal of the Transportation Research Board

9780309369299

Print

Figures (10) ; References (14) ; Tables (1)

Aggregates; Asphalt mixtures; Bituminous binders; Hot mix asphalt; Laboratory tests; Reclaimed asphalt pavements; Simulation

Highways; Materials; Pavements

TRIS, TRB, ATRI

Dec 30 2014 1:41PM

• Biomodification of Rubberized Asphalt and Its High Temperature Properties
• Characterization of Adhesion and Healing at the Interface Between Asphalt Binders and Aggregate Using Atomic Force Microscopy
• Correlating Laboratory Test Methodologies to Measure Skid Resistance of Pavement Surfaces
• Development of an Analytical Model to Predict the Field Permeability of Asphalt Pavements
• Effect of Mineral Fillers on the Oxidative Aging of Asphalt Binders: Laboratory Study with Mastics
• Effect of Recycling Agents on the Laboratory Performance of Asphalt Mixtures Containing Recycled Asphalt Shingles
• Effect of Water Content on Binder Foaming Characteristics and Foamed Mixture Properties
• Fatigue and Rutting Evaluation of Laboratory-Produced Asphalt Mixtures Containing Reclaimed Asphalt Pavement
• Fatigue Performance Evaluation of Rubberized Porous European Mixture by Simplified Viscoelastic Continuum Damage Model
• Improved Methodology to Evaluate Fracture Properties of Warm-Mix Asphalt Using Overlay Test
• Nanomechanical Evaluation of Vapor-Conditioned and Unconditioned Asphalt
• Numerically Supported Experimental Determination of the Behavior of the Interlayer Bond in Asphalt Pavement
• Precision of the Hamburg Wheel-Track Test
• Quantitative Characterization of Binder Blending: How Much Recycled Binder Is Mobilized During Mixing?
• Use of the Resilient Modulus Test to Characterize Asphalt Mixtures with Recycled Materials and Recycling Agents