Bird was the lead partner in a joint venture for the construction of the new vertical lift bridge in Placentia, NL. The scope of work consisted of replacing the Sir Ambrose Shea lift bridge, realigning the adjacent Route 100 roadway, and removing the existing bridge following completion of the new structure.
The project included the construction of two 58 m long temporary trestles using 600 mm pipe piles and a deck to support a 150 ton crawler crane. These trestles enabled the construction of two new central piers deep in Placentia Bay. The new lift bridge comprised approximately 9,290 m of 325 mm pipe piling; 2,200 m² of sheet pile used to form a cofferdam; 4,100 m³ of concrete; 1,000 tonnes of structural steel; and mechanical and electrical components required to allow the central lift span to open for marine traffic through the narrow water channel.
During construction, we encountered tidal ranges exceeding three metres combined with swift currents. Piling requirements for the south pier and south abutment increased substantially due to changes in geotechnical conditions, necessitating deeper driven piles. Following completion of the bridge substructure, structural steel was erected. The centre span presented the greatest construction challenge, requiring a temporary shutdown of the shipping lane to allow the installation of a 100 ton span. The completed bridge had an overall length of 100 m, consisting of two approach spans and a 30 m centre lift span.
