National Concrete Pavement Technology Center

Project description

Overlays are constructed over existing pavement structures as a repair measure. When an overlay is placed on an existing pavement, under thermal, shrinkage or traffic induced loadings, cracking of the overlay often takes place at locations where there are joints or cracks in the underlying pavement due to stress concentration. This phenomenon is known as reflective cracking. Reflective cracking in the overlay allows water to penetrate the pavement structure and contributes to many forms of pavement deterioration, including increased roughness, spalling and decreased fatigue life. Therefore, to achieve an effective and durable pavement repair using overlay system, reflective cracking needs to be suppressed. A ductile high-performance fiber reinforced concrete (HPFRC) interlayer is proposed in this research to mitigate the reflective cracking problem in pavement overlays. It is hypothesized that by adding a thin layer of highly ductile HPFRC material between the existing pavement and overlay, reflective cracking can be arrested by the ductile interlayer.