Dismantling and moving launching gantry Anne
The steps of a complex operation
Launching gantry Anne was successfully moved to the Anse-à-l’Orme terminal station on the West Island in mid-November. There, it was dismantled, then transported to the Pierrefonds-Roxboro borough for reassembly by the end of the year for its next mandate—building a 1.6-kilometre elevated section, starting in 2022. Here’s a look back at this major dismantling and relocation operation.
Launching gantry parts
Here are the various components of the launching gantries:
- Main beam – Two parallel main beams 110 metres long
- Rear support
- Frontal support
- Lifting beam
How was launching gantry Anne moved from Sainte-Anne-de-Bellevue to its new site?
The close collaboration of various partners, including the Ministère des Transports du Québec (MTQ) and the Ville de Montréal, was required to plan the launching gantry’s successful relocation. The move was done in phases, including many at night, to keep traffic congestion in the area to a minimum. Once the planning was completed, the operation began.
Here are the steps that were required to dismantle and move launching gantry Anne:
- Disassemble the parts of the launching gantry in order to isolate each of the main beams, place them on the ground using two 600-tonne mobile cranes at once, then move them by special convoy.
- In addition to shortening the length of each of the main beams from 110 metres to 87 metres to avoid possible road obstacles, one of the essential elements for moving the two main beams was the use of a self-propelled modular transporter (SPMT). This is a self-propelled modular trailer with a large array of wheels, all individually adjustable and steerable, controlled remotely by an operator via a computer. The SPMT safely navigated the route, adjusting to the different working conditions on the route by modifying load angles and height .
- Once the beams were securely fastened to their respective transporters (two transporters per main beam), they began their journey to their final destination, 11th Avenue in the Pierrefonds-Roxboro borough.
- In the last stage of its journey, the transporter travelled in the railway right-of-way to reach its destination, at the intersection of 11th Avenue and the REM route in the Pierrefonds-Roxboro borough.
Reassembling the gantry
At the destination, each of the main beams will be extended to their operational configuration of 110 metres. The three supports (auxiliary, rear and front) will be positioned on temporary towers provided for this purpose. The main beams will then be lifted one after the other by two 600-tonne mobile cranes and seated on the supports. The remaining parts of the launching gantry will then be reassembled and the gantry will be secured in mid-December 2021 for over-wintering.
During the winter of 2021–2022, the hydraulic and electrical components will be stored in a sheltered area and regularly checked. When it is started up again in spring 2022, the launching gantry will be checked by an approved engineering body before work resumes on assembling the spans.
The work to come for Anne and Marie in 2022
Once it arrives in Pierrefonds-Roxboro, Anne will have to assemble an elevated route of just over one kilometre between 11th Avenue and Des Sources Boulevard. Its twin, Marie, will be similarly relocated between Fairview-Pointe-Claire station and the intersection of Highway 40 and Henri-Bourassa Blvd. West in order to assemble the elevated segment to the Marie-Curie station in the Technoparc.