Developing Performance-Based Mix Design Framework Using Asphalt Mixture Performance Tester and Mechanistic Models.

Area of Science:

• Civil Engineering
• Materials Science
• Pavement Engineering

Background:

• Performance-related specifications (PRS) require linking pavement quality characteristics to predicted performance.
• Developing asphalt mix designs that balance fatigue and rutting resistance is crucial for pavement durability.

Purpose of the Study:

• To propose a performance-based mix design (PBMD) framework supporting PRS.
• To develop fatigue-preferred, rutting-preferred, and performance-balanced asphalt mix designs.
• To establish relationships between acceptable quality characteristics (AQCs) and predicted pavement performance.

Main Methods:

• Applied the PBMD framework to FHWA ALF materials using AMPT and mechanistic models.
• Developed nine asphalt mix designs varying in design VMA and air voids via the Bailey method.
• Evaluated cracking and rutting performance using DTC, TSS, and S-VECD models.

Main Results:

• Adjusting design VMA was the primary factor in meeting performance targets.
• Defined specific VMA ranges and performance criteria for fatigue-preferred, rutting-preferred, and performance-balanced designs.
• Pavement simulations confirmed that a layered PBMD approach minimizes cracking and rutting.

Conclusions:

• The proposed PBMD framework effectively guides the development of asphalt mixes with tailored performance characteristics.
• Optimized layering of fatigue-preferred, performance-balanced, and rutting-preferred mixes can significantly enhance pavement life.
• The study provides quantitative targets for AQCs to achieve desired pavement performance levels.