Balanced Mix Design: Evaluation of Cracking Tests for Airfield Pavements
Published August 2026
To address the limitations of traditional volumetric pavement design against rising gear loads and tire pressures, this research establishes a performance-based framework to accurately predict and characterize asphalt cracking in airport pavements. Drawing from extensive nationwide field sampling across diverse climates, the study delivers practical, scientifically validated testing protocols and provisional acceptance thresholds for potential integration into FAA Advisory Circular 150/5370-10H for both mixture design and quality control.
Download the full research report to access detailed specimen fabrication protocols, field validation data, and implementation guidelines for the three recommended cracking tests:
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Low-Temperature Cracking: Introduces the Simplified Low-Temperature Semi-Circular Bend (SLT-SCB) test, using a Low-temperature Cracking Index (LCI) threshold of 15 to evaluate crack initiation.
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Service-Temperature Cracking (I-FIT): Demonstrates that the Illinois Flexibility Index Test reliably identifies cracking susceptibility with a recommended Flexibility Index threshold of 7 on short-term aged specimens.
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Service-Temperature Cracking (DONUT): Replaces less reliable standard CT testing with the newly developed DONUT (Disc with O-Notch for Uniaxial Testing) protocol, utilizing a DONUT Index (DI) threshold of 6 to measure crack propagation speed.
