Analysis of Nondestructive Test Data on Flexible Pavements Acquired at the National Pavement Test Facility

This paper discusses the evaluation of the NDT and other test data with respect to:

1. Description of the FAA's new backcalculation software, FAA Backcal.
2. Linearity in pavement response and backcalculated subgrade modulus with applied HWD force. 
3. Comparison of the stiffness of conventional and stabilized base pavements on different subgrades.
4. Relationship between in situ California Bearing Ratio and backcalculated subgrade modulus.
5. The effect of stiffness of underlying layers on backcalculated subgrade modulus.

Authors: Roy D. McQueen, Wayne Marsey and Jose M. Arze