Treendale Bridge over Collie River
About the project
Scope
Earthworks including the excavation of the launch bed, and a walk path which ran underneath the northern side of the bridge
Construction of a launched steel composite box girder over Collie River
Design and construction of associated access tracks to and along the river bed, including crane pads
Design and construction of causeway to gain access for piling works in Collie River, including the construction of a pier requiring sheet piles and dewatering
Construction of associated drainage, lighting and electrical works
Construction of a possum bridge on both the northern and southern sides of the Collie River channel
Outcomes
BMD Constructions delivered the bridge structure through an alternate launch method, which saved on cost and time. BMD Constructions poured the bridge deck prior to launching, and then pushed the bridge superstructure from the bank out over the piers.
This method was adopted due to the very poor ground conditions on the southern side of the river, which would have been unable to support a large crane to lift the beams into place.
This technique was the second of its kind for client, Main Roads Western Australia, with BMD Constructions also successfully completing the Coolup East Bridge Replacement over Murray River in 2016.
BMD Constructions’ variation to the launch methodology reduced the number of launches leading to program efficiencies, which ultimately delivered the project ahead of schedule despite facing technical challenges throughout construction.