Reflective cracking is one of the primary causes of premature deterioration in asphalt-overlaid Portland cement concrete (PCC) pavements, reducing service life and increasing maintenance costs. Because crack initiation begins within the underlying PCC layer before becoming visible at the surface, conventional inspection methods have limited capability for early detection. This project developed and experimentally validated a hybrid experimental-numerical framework that integrates optical frequency domain reflectometry (OFDR)-based distributed fiber optic sensing (DFOS), laboratory-scale three-point bending tests, and finite element (ABAQUS) modeling to monitor and interpret bottom-up reflective cracking. Rectangular and semi-cylindrical asphalt-overlaid PCC specimens were instrumented with surface-bonded distributed optical fibers in a serpentine layout with 20-mm spacing. Controlled bending tests reproduced bottom-up crack initiation and propagation, with cracks consistently originating at a predefined notch within the PCC layer and propagating toward the asphalt overlay. The OFDR-based DFOS system identified localized strain concentrations associated with crack development; and finite element simulations reproduced the observed crack initiation location, propagation path, stress redistribution, and global structural response. The close agreement among laboratory observations, distributed strain measurements, and numerical predictions validates the framework and demonstrates the potential of OFDR-based DFOS for structural health monitoring and condition assessment of rehabilitated concrete pavements.

Infrastructure Assets: Highway Assets, Pavement
Resource Types: Research Report
Capabilities: Tools & Technology
Management Processes: Performance Based Planning & Programming