Bridges

The Pattullo Bridge Replacement Project (PBRP) involves building a new bridge to replace the existing Pattullo bridge over Fraser River in Vancouver, British Columbia (Canada).

The new bridge will consist of a cable stayed Main Bridge over the river, North and South Approach structures, associated ramps and other infrastructure upgrades on both sides of the river. Once constructed, the bridge will be configured with 4-traffic lanes plus separated multi-use paths (MUP's) on both sides.

The bridge design also makes provision for future widening to 6-traffic lanes also with separated MUP's on both sides.

This paper focuses on the South Approach structure and its interfaces with, primarily, two other new bridge structures on the south side of the river. The three structures cross various roads, rail lines and creeks in an area subject to significant archaeological, property, geotechnical and construction staging constraints. The complex structural arrangement needed to work around these constraints is discussed, as is the design provisions made to allow future widening.

Significant design effort was spent on seismic aspects of the design due to the site being in an area of high seismicity with deep liquefiable soil layers. Application of performance based seismic design as prescribed for such lifeline structures in Canadian Bridge Code CSA-S6-14 is discussed as is the chosen articulation scheme and use of seismic isolation bearings.

Design of large diameter steel pipe piles with deep reinforced concrete plugs is also discussed.