Rock Removal
Removing hazardous rock early prevents problems and emergencies down the road.
What is rock removal?
Rock removal is often a necessary first step in any rock face stabilisation project. In addition to eliminating longer‑term hazards, it is a critical measure for protecting site personnel prior to undertaking other works on or near a rock face.
The removal of small, loose material is commonly referred to as rock scaling or de‑scaling, while the removal of larger unstable sections is typically described as block removal or rock removal. These terms are often used interchangeably and reflect the scale and nature of the works rather than fundamentally different techniques.
How is Rock Removal carried out?
Rock scaling generally involves a hands‑on approach, requiring operatives to access the rock face using appropriate access methods. Hand tools are used to carefully remove loose or unstable material in a controlled manner, allowing debris to fall to a designated collection area for removal.
Larger block removal is typically employed where the risks associated with stabilising a hazard outweigh those of removing it entirely. In such cases, blocks may be restrained and lowered in a controlled manner, or, where appropriate, allowed to fall within managed exclusion zones.
A range of specialist techniques may be used, including:
- Heavy plant
- Power tools
- Mechanical jacks
- Winches
- Jacking
- Percussive breakers
- Plug and fealther
- Pneumatic airbag lifters
- Expanding grout systems
- Explosive charges (in exceptional circumstances)
The methods adopted are selected to suit the specific requirements of each project, taking into account factors such as location, rock mass characteristics, ground conditions, and site constraints.
This approach enables the most appropriate technique to be implemented to address immediate stability concerns, while also considering and managing the risk of longer‑term instability.
Risk Management
Where large or unstable rock blocks pose a risk to people, property, or critical infrastructure, a temporary restraint system may be installed to stabilise the rock mass.
This approach enables controlled breakout of the rock in situ and the safe, managed lowering of smaller debris, reducing the risk associated with uncontrolled collapse.
Due to the inherently unpredictable behaviour of rock masses once movement occurs, all work must be carried out with a clear understanding of the potential to induce further instability if not properly managed.
To manage these risks, we design and implement site‑specific protection measures, which may include:
- Engineered protective barriers
- Temporary catch fencing systems
- Controlled and enforced exclusion zones
