International heavy lift and transportation specialist Mammoet has been contracted by Canadian consortium Nouvel Horizon Saint-Laurent (NHSL) – which is made up of construction company Pomerleau and demolition specialist Delsan-AIM – to work on four different stages of the Champlain Bridge deconstruction project managed by the federal corporation The Jacques Cartier and Champlain Bridges Incorporated. The project is taking place in Montreal, Quebec, Canada.

The first span of the original Champlain Bridge was successfully taken down in early July. Around ten spans have been removed so far. For this Mammoet arranged a jacking system between a client-supplied catamaran barge and a demolition platform to lower concrete bridge deck sections weighing 1900 tonnes. Mammoet has provided six of its in-house developed jacking towers to effect this. Each tower of Mammoet’s MJS-800 system has an 800-tonnes capacity. The jacking towers are removing bridge deck spans as high as 25 metres (82 feet) above water level. Depending on weather conditions, the demolition of a span lasts around seven days.

At sections of the bridge where the water is too shallow for the barge and jack combination, this same system will be used to remove concrete bridge deck sections on temporarily reclaimed land. In this second stage the barge will be replaced by Mammoet’s self-propelled modular transporters (SPMT) to move the bridge sections away from their piers. The third stage is the removal of the steel truss sections above land with the same jack and SPMT combination.

Additionally, the job includes the removal of the steel truss bridge’s main span over the St. Lawrence Seaway. The 2,000 tonne (4,409,245 lb.) steel structure will be lowered down onto a barge using six Mammoet strand jacks.

The final challenge of the project will be to remove concrete bridge spans which are located over a busy highway. These spans will be safely removed over a weekend during a rapid bridge replacement — an activity which Mammoet said it has successfully performed multiple times in Canada and all over the world.

A video of the dismantling can be seen here: