A Screening Tool for Assessment of Moisture-Induced Damage of Asphalt Mixes Containing RAP Based on Molecular Dynamics Simulation
Infiltration of moisture into asphalt mixes leads to diminished performance, shortened lifespan, and unforeseen failures, thereby reducing the environmental and economic sustainability of road networks. Although the damage mechanism for moisture-induced damage was identified in the 1970s, the underlying fundamentals are not well understood. Also, most of the moisture-induced damage evaluation techniques rely on empirical test methods. In this project, the research team seeks to develop a screening tool for the assessment of moisture-induced damage potential of asphalt mixes containing reclaimed asphalt pavement (RAP). Molecular dynamics (MD) simulation, a widely accepted physics-based numerical simulation technique, will be used to examine the compatibility between asphalt binders and aggregates, including RAP. Because rejuvenators are used frequently in asphalt mixes containing RAP, particularly with increased RAP contents, rejuvenators will be included in the MD simulations. Adhesive interactions between asphalt binder and aggregate, in the presence of moisture, will be used as an indicator of compatibility or resistance to moisture-induced damage. Because of the limited budget and timeline, existing asphalt, aggregate, and rejuvenator molecules will be used in the MD simulations. Atomistic molecular dynamics will be used to simulate the binder and aggregate interfaces and determine the interaction energies and adhesive strengths between the binder and the aggregate. Bell’s model will be used to quantify the adhesion energy. The adhesive strength obtained from the MD simulations will be compared with the direct tensile strength determined in the laboratory using pneumatic adhesion tensile tests. The following tasks will be performed to meet the project goals: Task 1: determine adhesion energy following the procedure described in the literature; Task 2: determine the adhesion energy as a function of water concentration; Task 3: calculate the adhesion energy as a function of water concentration for selected additives or rejuvenators; Task 4: conduct laboratory tests to determine direct tensile strengths; Task 5: compare adhesion energy obtained from the MD simulations with the direct tensile strength results from Task 4, and Task 6: conduct a parametric study involving different parameters and develop an excel-based interactive spreadsheet that can be used by designers as a tool for evaluating aggregate-binder compatibility in presence of rejuvenators and resistance to moisture-induced damage of asphalt mixes. This project is expected to provide guidelines for improving the compatibility between asphalt binder and aggregate, with and without rejuvenators, in the presence of moisture. The Excel-based spreadsheet will be used to determine the optimum rejuvenator amount and binder-aggregate compatibility using the results from the MD simulations.
- Record URL:
Language
- English
Project
- Status: Active
- Funding: $96000
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Contract Numbers:
69A3552348306
CY1-LTU-02
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Sponsor Organizations:
Office of the Assistant Secretary for Research and Technology
University Transportation Centers Program
Department of Transportation
Washington, DC United States 20590 -
Managing Organizations:
Southern Plains Transportation Center
University of Oklahoma
201 Stephenson Pkwy, Suite 4200
Norman, OK United States 73019 -
Project Managers:
Dunn, Denise
- Performing Organizations: Ruston, LA United States 71272
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Principal Investigators:
Peters, Andrew
Wasiuddin, Nazimuddin
- Start Date: 20231001
- Expected Completion Date: 20240930
- Actual Completion Date: 0
- USDOT Program: University Transportation Centers
Subject/Index Terms
- TRT Terms: Adhesion; Asphalt mixtures; Moisture damage; Reclaimed asphalt pavements; Rejuvenators; Simulation
- Identifier Terms: Molecular Dynamics (Software)
- Subject Areas: Design; Highways; Materials; Pavements;
Filing Info
- Accession Number: 01899349
- Record Type: Research project
- Source Agency: Southern Plains Transportation Center
- Contract Numbers: 69A3552348306, CY1-LTU-02
- Files: UTC, RIP
- Created Date: Nov 15 2023 5:19PM