Blue Line Extension
Montreal
Context
As part of the Montréal Metro Blue Line extension, construction teams needed to implement an efficient solution to manage the large volumes of excavated material generated by tunnel excavation. The goal was to ensure the continuous management of excavated materials while maintaining an organized, safe, and functional worksite.
Challenge
The excavation work generated a significant volume of rock debris that needed to be removed quickly to avoid slowing down construction progress. The excavated material handling system had to be integrated directly in the excavation process while protecting the materials from the elements and providing sufficient storage capacity between transportation cycles.
The selected solution also needed to allow safe movement of the machinery used to collect the materials and withstand the demanding conditions of a large-scale construction site.
Solution
To meet these needs, a Permodome was installed to serve as a storage area for excavated materials coming directly from the tunnel. The excavated material was transported by a conveyor positioned to discharge the rock debris inside the dome, where it was temporarily stored before being collected by a wheel loader.
Thanks to its large, column-free interior space, the Permodome could accommodate a significant volume of material while facilitating machinery movement. Its structure also provided protection from the elements, allowing operations to continue even under the least favorable weather conditions.
Installation
The Permodome was installed at the heart of an active construction site, where careful coordination was essential to avoid disrupting the project’s progress. Each stage of the structure’s installation was carefully planned in collaboration with the on-site teams to integrate seamlessly with ongoing operations and meet the site’s requirements.
Despite constraints related to space, machinery traffic, and the fast pace of construction, the Permodome was erected while allowing ongoing work to continue. Once the structure was in place, the conveyor was installed to transport rock debris directly into the dome, where it could accumulate continuously before being collected by a wheel loader. This integration allowed the structure to become operational quickly and ensured uninterrupted operations throughout the excavation work.
Results
The integration of the Permodome ensured continuous management of excavated materials throughout the tunnelling operations without creating bottlenecks in the excavation process. Materials could be transported and stored efficiently, helping maintain a steady pace of work on the construction site.
By centralizing the accumulation of rock debris in a dedicated and protected area, crews were able to keep the site better organized and reduce unnecessary material handling. The open interior space also facilitated the removal of excavated materials using heavy equipment, making the material management cycle more efficient.
In the context of an active and constrained construction site, this solution helped support the progress of excavation work by reducing interruptions related to material management and improving the overall flow of on-site operations.
