Site C Clean Energy Project | Fort St. John, British Columbia

Stability and Strength with EFCO Jump Brackets

The Site C project’s powerhouse is at the heart of its operations, where the generated power will be transferred to the grid. EFCO’s SUPER STUD Jump Bracket System, combined with E-BEAM & SUPER STUD wall forms, was used to handle the tall vertical structures, allowing for precise and rapid construction. SUPER STUDs were used as stiffbacks on the wall forms, simplifying the process with minimal or no teardown required for cycling, which reduced the need for rework. Additionally, the Jump Brackets provided the versatility needed for tall walls while offering a safe and efficient formwork cycling system.

EFCOs E-Z DECK® high-capacity shoring system supported the powerhouse’s multi-level pours, making sure that all concrete work met the structural integrity requirements. E-Z DECK, an aluminum high-capacity shoring system, can be both handset and ganged for a max load of 28 kips (124.5kN)per post. Tall E-Z DECK towers can be built horizontally on the ground and lifted into place, minimizing aerial work and decreasing erection labor with safe on-the-ground assembly. The contractor selected EFCO’s systems for their ease of assembly and interchangeable parts.

Handling Height and Precision with HDS-100

The intakes, critical to channeling water into the powerhouse for energy generation, required EFCO’s HDS-100 system to support immense loads during construction. With heights exceeding 60 feet (18.5m), stability was a requirement, and EFCO’s shoring systems delivered both strength and safety.

The HDS-100 system was selected for its ability to handle high loads while providing the flexibility needed to adjust for the unique geometry of the intakes. By using EFCO’s systems, AFDE reduced the required support points, allowing for faster construction and lower labor costs. The system’s modular design towers were assembled on rails, which allowed them to be pulled out from under the roof pour. This design gave AFDE enormous labor savings, allowing for minimal tear-down and cycling to the next intake. This made it easy to cycle the assembled towers from one pour to the next.

Cantilever Wall System for Unmatched Efficiency

EFCO’s CWS (Cantilever Wall System) played a key role in the construction of the headworks, stilling basin, and spillway. These areas required tall, reinforced walls capable of withstanding extreme water pressure, and EFCO’s CWS allowed the contractor to form these walls without the need for form ties. EFCO’s CWS brackets resist concrete pour pressure through a single anchor in the previous concrete pour instead of using form ties. Frames were spaced at 4ft (1.2m) centers and formed pour heights up to 10ft (3m) tall.

The CWS also featured a roll-back design, allowing the wall forms to be rolled back and forth into place for inspection, pouring, and stripping. This system allowed for ganging assemblies with up to five CWS frames assembled on the ground and lifted into place with a crane, enhancing worker safety and efficiency.

The contractor chose EFCO’s CWS not only for its innovative design but also for its ability to speed up construction and provide predictable deflection during pours, as the concrete tolerance for areas with high-velocity water flow demanded a formwork system that left minimal concrete finishing.

Curved Forming with Precision and Power

One of the project’s most visually impressive parts, the spillway, required complex curved forms to manage excess water flow. EFCO’s SUPER STUD and CWS systems allow for easy transitions between vertical and sloped surfaces while handling the curvature and high loads. EFCO Provided radius-specific wood shims that were easily attached to the SUPER STUD stiffback, allowing for a curved form design.

The spillway’s design required high-load-bearing formwork that could be cycled efficiently. EFCO’s field service team provided hands-on support to ensure the spillway’s unique curved elements were formed flawlessly. By using SUPER STUD and CWS, AFDE achieved the complex shapes required while reducing the finishing labor needed for each pour.

Why AFDE  Chose EFCO

AFDE chose EFCO for the Site C project for several reasons: commitment to Quality, Innovative formwork solutions, and dedication to Super Service. They also chose EFCO for their ability to supply a vast amount of formwork and shoring from their extensive North American lease pool. This decision helped AFDE reduce cycle times, minimize material needs, and enhance worker safety—leading to lower overall costs and ensuring the project stayed on schedule. EFCO’s formwork systems played a crucial role in meeting the project’s demands while helping AFDE achieve the Lowest In-place Concrete Cost (LIPCC).