The Louis-Hippolyte-La Fontaine tunnel-bridge complex, as its name implies, is divided into two sections: the tunnel part of a length of 1.4 kilometer, linking the Island of Montreal to Île- Charron, and the bridge part that connects Île-Charron to Longueuil over a length of 457 meters. The Tunnel is considered a very important submerged tunnel in Canada and opened in 1967. It is managed by the MTQ and allows 120,000 vehicles to cross the St. Lawrence River daily. The initial construction cost was $75 million.
The Tunnel has deteriorated over the 50+ years of its existence due to chloride-induced corrosion. A major refurbishment of the tunnel began in 2020, which is to be completed in 2025. The Tunnel is one of top 50 largest infrastructure projects in Canada with total project value of $2.1 billion. The tunnel includes service tunnel, southbound and northbound tunnels.
The main objectives of corrosion protection are to provide a minimum of 20 years corrosion protection by galvanic anodes and ensure the sustainability of the infrastructure, including the goal of operating without major long-term obstacles for 40 years. Galvanic cathodic protection provides an effective low maintenance option for engineers and owners of infrastructure. The service tunnel has been patch repaired and protected with discrete galvanic anodes, while the traffic tunnels will be refaced and protected with distributed galvanic anodes.
This presentation includes the studies of different corrosion protection options, design and implementation of corrosion protection system.
