The $38 million upgrade of the Tinana Interchange section of the Bruce Highway involved realignment of realignment of the off ramps, additional lanes, the demolition and re-construction of a new overpass bridge. 

CGC provided the detailed design of the 130m abutment reinforced soil structure retaining walls for the construction of a new overpass over the Bruce Highway. The geotechnical design included sliding, bearing and overturning analysis of the retaining walls, global slip analysis and settlement analysis. 

Challenges included a variable backslope profile and the bridge abutment not perpendicular to the wall, requiring the development of detailed geotechnical models.