Reflective Cracking Outdoor Phase 2


      • Cracking in the HMA Overlay: One bottom-up crack was observed during HVS-A trafficking at the West edge of the TT56 joint.
      • HMA Overlay Strain Distribution: Strain distribution in the HMA overlay varied based on the joint type (doweled or undoweled) of the PCC layer. Doweled PCC joints showed a uniform strain distribution throughout the HMA overlay, whereas undoweled joints showed a top-down strain distribution with tensile strains at the surface and compressive strains at the bottom of the HMA overlay.
      • Temperature Distribution: Internal temperature in the HMA overlay was greater than the ambient temperature due to sunlight exposure on the HMA overlay and the internal temperature in the HMA layer was not uniform with a peak value at the mid-depth of the HMA overlay.
      • Joint Displacement: Temperature change showed to have a greater impact on PCC joint displacement compared to trafficking.
      • HWD Testing: HWD testing showed a decrease in the backcalculated modulus of the HMA overlay at most joints indicating structural deterioration in the HMA overlay between RCOD Phase I and RCOD Phase II.


Click Here to Access the Reflective Cracking Outdoor Phase II Database 

Download the Reflective Cracking Outdoor Phase II Comprehensive Report



Reflective Cracking Outdoor Phase 2


The primary objective of Reflective Cracking Outdoor (RCOD) Phase II was to evaluate the performance of HMA overlays when exposed to temperature changes and aircraft trafficking. 

Specifically, RCOD Phase II included:

      • Perform additional accelerated aircraft trafficking on the RCOD TT section
      • Measure strain responses in the HMA overlay under aircraft trafficking
      • Conduct visual distress surveys to document any visual cracking
      • Analyze daily temperature and joint displacement measurements
      • Assess changes in structural capacity using nondestructive testing (NDT)