The Rosedale Overhead is a 77m long two-lane crossing of BC’s Highway 9 over a busy railway track.
Built in 1956, the current improvements include widening, new barriers, seismic retrofit and
structural rehabilitation, including full concrete deck replacement. The initial design considered
retaining and over-coating the existing girders. However, the final design was the outright
replacement of the existing girders, with the new girders configured as continuous spans. This
concept was preferred because of the lower costs, a savings partly attributed to the reduced number
of girder lines from eight to five and bearings by more than half. A reliable seismic load path was
established by infilling the bents either side of the rail tracks and locking the bridge ends with new
semi-integral abutments. All other bents were left un-retrofitted with low-friction PTFE bearings to
reduce lateral bent demands and avoid foundation upgrades.
O’Hagan, S., K. Holmes, R. Saiedi, S. Khan and B. Hamersley. 2017. “Rosedale Overhead: Functional Upgrades, Structural Rehabilitation and Seismic Retrofit,” in 39th IABSE Symposium – Engineering the Future, September 21-23 2017. Vancouver, Canada.