Here's when and why it is used:
1. Initial Support (Shotcrete Application)
After Excavation: As soon as a section of the tunnel is excavated, a trucked concrete pump is used to spray shotcrete onto the tunnel walls for initial stabilization.
Rock Reinforcement: Shotcrete is applied in combination with rock bolts and steel mesh to strengthen weak rock formations.
Preventing Loose Rockfall: It helps control rockfall and stabilizes the tunnel walls before additional support structures are installed.
2. Secondary Support (Final Lining)
Casting Tunnel Liners: The pump delivers concrete for permanent tunnel linings, ensuring a smooth and strong interior surface.
Backfilling Gaps: Used to fill gaps between the primary support and the final lining to improve load distribution and stability.
3. Repair and Maintenance
Structural Reinforcement: Used for injecting concrete into cracks or damaged areas for long-term tunnel safety.
Waterproofing Support: In some cases, shotcrete with waterproof additives is pumped to prevent water ingress.
Why Use a Trucked Concrete Pump?
Mobility: Easy to move within or outside the tunnel.
High Pressure and Reach: Can pump concrete to difficult-to-access tunnel sections.
Continuous Concrete Supply: Ensures a steady and efficient application.
Would you like details on specific pumping techniques or equipment recommendations?
