Toronto Eaton Centre Footbridge
Introduction
The Toronto Eaton Centre (TEC) is connected to Hudson’s Bay and Saks Fifth Avenue via a footbridge that runs across the road between the two buildings (Queen Street’s West). The bridge has a span of 35m and weighs 200 tonnes. It joins the two buildings on the third floor. After 40 years of use, the old bridge had to be replaced. It is comprised a metallic frame running across from one building to the other with semi-circular trusses separated by glass panels alternating the length of the bridge. According to the Toronto Eaton Centre’s press release, the new bridge was designed to enhance aesthetics and functionality.
Structural form
The bridge connects to Hudson’s Bay and Saks Fifth Avenue via circular arches. Brass portals twist out from the circular arch and resolve into a strictly rectangular shape that connects to TEC. The bridge is supported by an 88-ton box girder beam that spans the bottom section. 200 etched bronze panels alternating with and 355 slumped glass panels form a gradual transition between the two buildings (PCL Construction, 2018). According to the construction company, no two pieces of glass or bronze are similar. Each piece was designed for a specific section. The glass and bronze panels enclose a tunnel with the box girder beam carrying the load on the bottom and also acting as the floor.
Construction Issues
Constructing the bridge was particularly demanding due to considerations of interruptions of foot and vehicle traffic. Removing the former bridge and replacing it with the newly constructed one had to be completed in a very tight timeline. To avoid traffic interruption, the new bridge was assembled on the adjacent James Street. This entailed delivering the brass and glass plates, the primary and secondary steel structure, and any components and tools required to James Street where they were then assembled on a temporary platform. On completion, a modular vehicle raised the bridge with the help of hydraulics and then delivered it to its final position on Queen Street West in readiness for lifting it and fitting it into place. The process required closing the busy road for 2 weekends. The bridge was completed and opened for use on November 2nd 2017 (Canadian Architect, 2018).
Sustainability
Brass is very easy to machine and the process is not energy intensive therefore the construction can be considered sustainable. Further, etched brass is very resistant to corrosion and as such the outer façade of the bridge will sustain its aesthetic appeal for a long time. The materials used are also very recyclable.
Pros and Cons
The façade of the bridge was fabricated using brass which is very long lasting and corrosion resistant. The colour also gave it a large aesthetic appeal. However, the outer glass surface will require continuous cleaning and could be susceptible to breakages. The central girder, being fabricated from steel, is susceptible to corrosion.
Comparison with another Bridge
The Harthill Bridge in Scotland spans a longer length across the M8 and is constructed using steel trusses. The central girder of the TEC Bridge is also fabricated from steel providing the much-needed strength. However, steel was not used for the outer structure since brass is more appealing and corrosion resistant.
References
Canadian Architect. (2018, July 15). WilkinsonEyre and Zeidler’s Eaton Centre Bridge installed in Toronto. Retrieved from The National Review of Design and Practise: https://www.canadianarchitect.com/architecture/eaton-centre-bridge/1003739147/
PCL Construction. (2018, February 16). CF Toronto Eaton Centre Bridge Project Named Best of the Best. Retrieved from: http://www.pcl.com/News-And-Media/News-Releases/Pages/CF-Toronto-Eaton-Centre-Bridge-Project-Named-Best-of-the-Best.aspx
