Radio Frequency Identification Applications in Pavements

RECOMMENDATIONS FOR FUTURE WORK

Recommendations for follow-on work after this project include the following:

• Commercialization of the RFID system for tracking HMA placement. This research has demonstrated the success of the concept. However, it was impossible to generate commercial interest in it during the course of the project.
  
  
• Evaluation of other RFID systems (e.g., different frequency range, active instead of passive system, etc.) for use in tracking PCC placement. The high dielectric constant of the cement paste coating the aggregates in PCC makes it impossible to pass a sufficiently strong signal to/from the passive UHF RFID tags used so successfully for HMA tracking.
  
  
• For temperature measurement using SAW RFID tags, more work should be done to determine the minimum thickness of the epoxy coating to maximize tag readability and minimize thermal lag while still ensuring survivability. Additional work in collaboration with the SAW RFID system manufacturer is required to optimize the temperature window in the reader so that the early rapid cooling trends of the mat can be captured. Field trials should also be repeated on thicker HMA layers in which the variation of temperature with depth is more pronounced.
  
  
• Laboratory evaluation of the reflection crack detector should be conducted using a Texas Overlay Tester instead of three-point bending to better simulate how overlays fail. Through these tests, the CMOD as a function of vertical crack propagation can be determined more accurately, and the crack detector design can be adjusted as needed. Laboratory evaluation should then be followed by field trials on in-service pavements. The duration of these field trials would need to be on the order of 5 to 10 years to allow sufficient time for reflection cracks to initiate and propagate.