
Heavy-lift specialist Mammoet has won a contract to help replace the dysfunctional roof at Montreal’s 55,000-seat Olympic stadium, built for the 1976 Olympics.
It will provide mobile cranes for the demolition of the old roof, and deploy its Mega Jack 5200 system to lift the new roof 50m up for fixing into place.
A joint venture of Canadian contractors, Pomerleau and Canam, won a US$542m contract to replace the fragile roof a year ago.
The roof was replaced in 1999, but has since deteriorated. Currently, the stadium can’t be used for half the year because of its fragility, since events are cancelled if more than 3cm of snow are forecast.
The contracting JV’s task is to replace the oval section surrounded by the roof’s concrete ribs.

German architect GMP has designed a new oval covering with an opaque upper skin surrounded by a ring of glazing to let natural light in.
It will be built inside the stadium on temporary supports, then Mammoet will lift it with six Mega Jack towers.
Strand jacks will stabilise the roof as it is raised.
Up for two months
The roof will stay raised on the jacking systems for two months for the installation work, which includes attaching the roof by cables to the stadium’s 165m-high inclined tower, La Tour de Montréal.
Mammoet has also designed special final adjustment devices to sit on the top of each lifting tower. Taking the form of miniature skidding tracks, these allow precision positioning of the roof once it is at the required height.

“Throughout the planning phase, they have demonstrated their expertise, coordinating a bespoke solution to get the new structure lifted, positioned and ready for installation,” said Serge Néron, deputy project director at the contracting JV.
The project was scheduled to finish in 2028 when the Pomerleau-Canam JV was appointed.
The operation will be managed through Mammoet’s Canada East subsidiary, which employs around 500 heavy lifting and transport experts in Ontario and Quebec.
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