Benmokrane reached out to MTO, MMM Group (now known as WSP) and Buckland & Taylor to design 480 3 x 7-meter GFRP-RC deck panels, as well as sidewalks with 15- and 20-millimeter-thick GFRP-RC rebar. A total of roughly 350,000 meters of GFRP bars were used in the bridge deck. The GFRP was supplied by V-Rod Canada, which has supplied composite materials for hundreds of bridges for the MTO and other owners across the country. All of the panels were fabricated and cast at a precast facility (M CON Pipe & Products Inc., Ayr, Ontario, Canada) and then shipped onsite.
Two construction firms, Bot Construction and Ferrovial Agroman, accelerated construction by precasting the panels in pylons and connecting them with UHPFRC joints. After building the deck, Bot and Ferrovial drove 182 steel piles 50 to 70 meters deep for a cast-in-place substructure that is 75 meters high when measured from the bridge’s foundation footings. They then placed the precast, multi-beam center pier about 51 meters above the deck. The beams are connected to the bridge by 66 steel cables.
The bridge has been built in two halves. The westbound section was finished in November 2015, while the eastbound span is scheduled for completion this year.
Benmokrane and his research team at Sherbrooke have made recommendations to install fiber-optic sensors on critical parts of the bridge to measure strain and temperature data. The data, he says, will allow his team to assess the bridge under actual service conditions. The team will also conduct live field tests to assess the bridge’s long-term durability and serviceability in a wide range of environmental and traffic conditions.
Benmokrane believes the bridge is a landmark achievement for the composites industry as it looks to further expand into the infrastructure market. During the International Bridge Conference in National Harbor, Md., Benmokrane made a presentation on the design of the bridge and the benefits of FRP. He says he was happy with the feedback he received from engineers at the conference and is optimistic that applications like the Nipigon River bridge can open doors for many composites businesses.
“Based on the feedback I’ve been getting, I’m really expecting that in the future we will see many more bridges all over the world that use this kind of reinforcement,” says Benmokrane. “These bridges are very economic, elegant and have a great aesthetic.”
He says concrete bridges reinforced with GFRP rebars have an initial cost that is almost the same as concrete bridges reinforced with epoxy-coated or galvanized steel rebars. He adds stainless steel rebar is also two to four times more expensive than GFRP rebar.