Arch bridge

Several structures were slated for construction as part of the project to build a four-lane dual carriageway between Quebec City and Saguenay. This included a bridge that would connect the existing Route 175 to the future Highway 73 in the Stoneham-et-Tewkesbury region, located 30 km north of Quebec City. Once the mandate was granted by the Ministère des Transports du Québec (MTQ), CIMA+ proceeded to identify which structure was most appropriate for the location and for established constraints. The firm then designed the structure and carried out on-site supervision of the work.

The CIMA+ team was convinced it was possible to build a bridge with a thin deck that would meet vertical clearance constraints under the structure and minimize rock excavation. CIMA+ proposed an original solution that was both cost-effective and aesthetically pleasing: an arch bridge. This design did not require the construction of a pier in the central median and would not incur any modifications to the proposed profiles of Highway 73 and Talbot Boulevard due to the shallowness of the deck. This type of bridge design is not common in Canada, and is only the second of its kind to be built on Quebec’s road network in the last 50 years.

The Stoneham-et-Tewkesbury arch bridge is currently in use and all inspections it has undergone since its opening, including the first general inspection conducted by the MTQ in June 2011, allowed us to conclude that the structure meets design expectations. The bridge was designed by CIMA+ so that it would retain its functionality in the event of a major accident or earthquake that could damage one of the cables supporting the deck.

CIMA+ was proactively involved in the completion of this project by supervising the construction site and delegating a highly experienced team. In fact, the supervisor’s planning for any potential construction problems, especially with regard to the two concrete arches, led to the success of this project whose lifespan is estimated to be over 75 years.

CIMA+’s standards of excellence were recognized. In 2012 this project received an Association des ingénieurs-conseils du Québec award in the Transportation category.