Design and Performance of Unbonded PCC Overlays
Due to increased traffic congestion and reduced highway construction budgets, emphasis has been placed on seeking effective rehabilitation techniques for older pavements. Whitetopping and unbonded concrete overlays have great potential as pavement rehabilitation methods. Design thicknesses for these overlays tend to be greater than 7 inches. Due to the large initial cost of constructing these relatively thick layers (which includes costs associated with raising of the shoulders, bridges, and intersections), there is interest in understanding the performance of thinner unbonded concrete overlays.
NRRA is fortunate that MnROAD has constructed and instrumented thinner concrete unbonded overlays and whitetopping.
There is also interest in providing more information on types on interlayers for concrete overlays including new HMA, drainable coarse asphalt, milled/aged HMA, geotextile bond breaker. Guidance on what value these interlayers provide in the pavement design needs to also be explained.
Original Need Statement: Design and Performance of Concrete Unbonded Overlays (doc), August 8, 2016
Project Technical Advisory Panel (TAP):
- Tim Andersen, MnDOT
- Tom Burnham, MnDOT
- Maria Masten, MnDOT
- Charles Wienrank, Illinois DOT
- Jim Wilde, MSU
- Zhanping You, MTU
Final published report (pdf), October 2020