Roads & Highways
Mountain Road Rehabilitation
A 6.8-kilometre rebuild of a frost-damaged mountain road, with a new pavement structure, wider shoulders and 22 replacement culverts.
- Year
- 2021
- Client
- Regional road authority
- Location
- Mountain pass corridor
- My role
- Design engineer and resident engineer
The challenge
Freeze-thaw cycles had broken up the old pavement, and undersized culverts were sending meltwater across the road every spring. The authority needed a road that would last twenty years and could be rebuilt in a single short construction season while the route stayed open.
The approach
Pavement cores and deflection testing showed exactly where the base had failed. I designed a frost-protected pavement with a free-draining layer and full-depth reclamation in the worst sections, and resized every culvert for a 50-year storm with spring melt added on top.
- Pavement design based on measured traffic counts and deflection testing
- Hydrology for 22 crossings, each with its own catchment
- Staged traffic plan so the road never fully closed
The outcome
The road was handed over two weeks ahead of schedule. Two springs later there are no reported washouts and no frost heave in the rebuilt sections.