09/12/2024
Syblon Reid was awarded a project for a northwest hydropower company in July 2023. The team executed detailed planning for access, demolition, drilling, grouting, concrete placement, and water management. Access was primarily through the spillway intake structure, with a scaffold stair tower and temporary guardrails ensuring safety. For the inclined tunnel section, a traveling platform supported by hydraulic winches and accessed via a heavy-duty swing stage was employed.
Drilling and grouting focused on water intrusion and reinforcing the substrate layer with cementitious and polyurethane grout injection. Demolition included radial saw cutting and selective removal of concrete using a remote-controlled hydraulic demolition machine.
The project utilized a self-consolidating concrete mix to ensure smooth application and high-quality coverage. Custom-designed radial wood forms, anchored with coil rod anchors, were used to match the tunnel’s curvature. Concrete was pumped through ports on these forms using a line pump and tremie tubes, ensuring consistent distribution and avoiding segregation. This approach, combined with advanced formwork techniques, led to successful and efficient aerator system placement.
Despite facing initial delays and a tight schedule, the project prioritized safety with zero loss-time incidents. The Contractor-designed access platform proved effective, and while drilling revealed substrate issues affecting stability, the team overcame challenges with innovative water control and demolition methods. The use of advanced concrete technology resulted in a high-quality finish and overall project success.
