Tourists disembarking from their cruises in Montreal’s Old Port now benefit from a new aluminum pedestrian bridge that links up with the second floor of the Alexandra Iberville maritime terminal.
September 29, 2017—Montreal, Canada – Designed, manufactured, and installed by MAADI Group, the prefabricated aluminum structure, called a skywalk, was part of a $78-million dollar restoration of the Alexandra Pier and Iberville Passenger Terminal. The restoration project, under the aegis of the Montreal Port Authority, was funded by investments from the municipal and provincial governments to help modernize and integrate the aging maritime structures into the urban fabric of Old Montreal.
Measuring 32 m (105 ft.) in length and weighing 9.15 metric tons (10.1 tons), the skywalk required an extra-wide truck and a police escort to transport it through the narrow streets of Old Montreal.
The installation itself, which could only take place when no boats were in port, went smoothly. That ease was due to the tight collaboration between MAADI Group, which won the public tender, and Pomerleau, the construction company managing the project. Their collaboration began even before the skywalk was designed.
“What was very important for us regarding the skywalk,” said Marc Plamondon, Pomerleau’s Project Manager, “was the precision [measurement] of the concrete footings, the precision [measurement] of the axes.” Given that the foundations of the buildings dated from the early 1900s, the axes of the columns and pillars were not perfectly centered. “So during the development, design, and fabrication of the skywalk,” said Plamondon, “it was important to respect the measurements, which were very precise.”
In fact, due to the structural irregularities of these old but very solidly constructed buildings, the skywalk extends about 2.4 m (7.9 ft.) into the buildings at either extremity. “The skywalk rests on the two existing buildings, and other things,” said Philippe Beaudoin, the engineer who is managing the structural aspects of the entire Iberville restoration project on behalf of NCK Inc. “We did not have to build new footings to support the skywalk.”
At the beginning of the project, NCK determined the loads that had to be considered in the development of the skywalk. Complying with CAN/CSA-S6-14 (2014) (Canadian Highway Bridge Design Code), the skywalk has the capacity to handle a one-tonne (2,240 lb.) vehicle and pedestrian traffic of 4.8 kPa (100 psf). The bridge is made of plates of aluminum alloy 5083-H321 and extruded aluminum 6061-T6. The fusion welding complies with CSA Standard W47.2, which requires companies to be certified for Fusion Welding of Aluminum, and CSA Standard W59.2-M1991 (R2013), for Welded Aluminum Construction (an equivalent to AWS D1.2).
With a clear width of 2 m (6.6 ft.), the floor of the skywalk is made of fire-resistant planks of red cedar from western Canada that have a 64 mm (2.5 in.) finished thickness.
The architectural firm Provencher_Roy did not use vertical-post fencing to provide pedestrian protection along the guard rails. Instead, inspired by the maritime location, the design called for a stainless steel mesh, reminiscent of fishing nets, made of 40 mm x 40 mm (1.5 in x 1.5 in.) squares hand-woven in a “Lock-Tuck” construction. Made of small-gage stainless steel wire, the mesh creates great transparency and a more pleasing architectural look when viewed from streetside in the Old Port of Montreal.
The skywalk “seems to float a little in the air,” said Sonia Gagné, partner at Provencher_Roy and the architect in charge of the Iberville terminal restoration. “The client [Montreal Port Authority] is really impressed. It’s a very nice acquisition, I think, for the Port.”
The skywalk is easily visible from the Old Port by day and by night due to a remote-controlled RGB LED lighting system. Thirty-four “uplight” type headlamps with a diameter of 70 mm (2.8 in.) provide the dimmable illumination. This technology enables one to zone light fixtures in up to 250 groups or change the light’s color to one of 30,000 options via RGBW LEDs.
“This renovation of the Iberville Passenger Terminal will make thousands of cruise tourists feel even more welcome in Montreal,” said Alexandre de la Chevrotière, CEO of MAADI Group. “The big advantage for the Port is that aluminum is corrosion-free, so it has a low cost of ownership compared to other materials such as steel, which always requires maintenance to prevent corrosion. We are proud to have one of our pedestrian bridges showcased in such an appealing setting.”