Improved Overlay Design Parameters for Concrete Airfield Pavements - Structural Condition Index (SCI) Validation Study

Pavement Engineering: Design-Build
Pavement Engineering: Research: Performance
Key Services: 
  • Rigid Pavement Design-Build
  • Structural Condition Index (SCI) Validation
  • Pavement Research

Validate the Structural Condition Index (SCI) and the impact of the scale upon the performance of rigid overlays.

QES' responsibility for this project was to provide validation of the Structural Condition Index (SCI) and the impact of the scale upon the performance of rigid overlays to provide policy makers with a tool that can be used to determine the influence of the sub-slab condition with respect to the performance of a rigid overlay. The primary focus was to determine the effects of varying degrees of deteriorated underlying slab conditions on overlay performance. To accomplish this, QES designed a new rigid overlay, using the observed SCI condition, to develop correlations between the constructed thickness and the passes to different levels of induced distress. The new overlay was then constructed over an entire length of pavement, incorporating load transfer variations, to determine the structural response and impacts on the observed distress mechanisms. Separate test sections were used for loading, using the dual tandem and tridem gear configurations. QES then removed the overlay and examined the underlying pavement to verify the deterioration mechanisms that were predicted or recorded by the instrumentation.