6 Critical Applications of Rockbreakers in Tunnel Construction: Speed & Safety

Tunnel construction is one of the most complex engineering challenges in the world. Whether carving through the Swiss Alps or digging a subway line beneath a bustling metropolis, the geology dictates the pace.

While Tunnel Boring Machines (TBMs) get the headlines, the Rockbreaker is the versatile workhorse that handles the tasks a TBM cannot. From the initial shaft sinking to the precise trimming of tunnel walls for support installation, hydraulic breakers are indispensable.

Furthermore, managing the flow of excavated rock requires specialized equipment. This is where Rock Breaker Booms Systems play a pivotal role in ensuring that underground crushers and grizzlies never get blocked.

Here are the 6 specific applications where rockbreakers are transforming tunnel construction.

1. Primary Tunnel Excavation (Drill & Blast Alternative)

Not every tunnel allows for blasting.

• The Scenario: In short tunnels or areas with sensitive geology (soft rock or mixed ground), using explosives is too risky or expensive.

• The Application: Rockbreakers mounted on excavators act as the primary excavation tool. They mechanically fracture the rock face (heading), allowing for a continuous "advance" without the stop-start cycle of drilling and blasting. This is particularly effective in "Roadheader" style excavation for irregular tunnel shapes.

2. Removal of Temporary Walls & Structures

Tunneling often involves complex staging.

• The Role: Projects often require temporary concrete retaining walls or pilot tunnel linings to stabilize the ground before the final bore is completed.

• The Precision: A rockbreaker allows for the surgical removal of these temporary structures. Operators can chip away concrete inches at a time without damaging the permanent tunnel lining or disturbing the surrounding soil.

3. Shaft Sinking and Vertical Excavation

Before you can tunnel horizontally, you often need to go down vertically.

• The Challenge: Excavating ventilation shafts or access pits is tight, difficult work.

• The Application: Rockbreakers are essential for breaking rock at the bottom of the shaft. Their ability to deliver high-impact energy in a vertical position makes them the fastest method for deepening shafts where blasting is not feasible due to vibration concerns.

4. Surface Preparation for Support Installation

A tunnel is only as safe as its support system.

• The Task: Installing steel arches, shotcrete, or rock bolts requires a specific tunnel profile.

• The Application: Rockbreakers are used for "scaling" and "profiling." They trim the uneven rock surfaces left after blasting, creating a smooth contour. This ensures that steel support beams fit correctly and that shotcrete adheres properly to the wall, guaranteeing structural integrity.

5. Excavation of Drainage and Utility Tunnels

Not all tunnels are for cars or trains.

• The Niche: Small cross-section tunnels for drainage, cables, or sewage often have limited access.

• The Flexibility: Compact rockbreakers can operate in these confined spaces where larger machinery cannot fit. They are the standard solution for excavating the "invert" (the floor of the tunnel) to lay drainage pipes and high-voltage cables.

6. High-Efficiency Mechanized Operations

Safety in tunneling means removing humans from the danger zone.

• The Shift: Modern tunneling relies on mechanization to handle rock in areas too dangerous for manual labor.

• The Solution: In large-scale tunneling projects involving underground crushers or "grizzly" screens (ore passes), stationary Rock Breaker Booms Systems are installed.

• The Benefit: These systems allow operators to clear rock blockages remotely. This keeps the excavation material moving out of the tunnel efficiently while keeping personnel safe from falling debris or crush hazards.

Conclusion

In the claustrophobic and high-pressure environment of tunnel construction, reliability is everything. The Rockbreaker provides the flexibility to handle unexpected geological changes, from soft clay to hard granite.

For major infrastructure projects, the integration of stationary Rock Breaker Booms Systems at underground transfer points is the key to maintaining high production rates. By preventing jams in the material handling system, you ensure the tunnel advances on schedule.

Keep your underground operations flowing.Discover our specialized breaking solutions designed for the rigorous demands of tunneling and mining.

FAQ (Frequently Asked Questions)

Q1: Why use a rockbreaker instead of blasting in tunnels?

A: Blasting creates toxic fumes (requiring ventilation time), ground vibrations (risking collapse or surface damage), and over-break (removing too much rock). Rockbreakers offer a continuous, controlled, and immediate excavation process without these side effects.

Q2: How does a Rock Breaker Boom System help in tunneling?

A: In long tunnels, excavated rock is often dumped onto a conveyor or into a crusher underground. A stationary Rock Breaker Booms System is placed at this dump point to break oversized rocks that would otherwise block the conveyor, ensuring continuous muck removal.

Q3: Can rockbreakers work in vertical shafts?

A: Yes. Excavators can be lowered into the shaft, or specialized telescopic boom arms can be used. The rockbreaker is the most efficient tool for breaking rock at the shaft floor where drilling equipment is hard to position.

Q4: What is "scaling" in tunneling?

A: Scaling is the process of removing loose rock from the tunnel roof and walls after excavation. While often done manually in the past, mechanical scaling using a rockbreaker or a scaling tool is now the standard safety practice to prevent rockfalls.