What is conventional tunnelling?
Conventional tunnelling is a construction method in which excavation and ground support are carried out in successive steps or cycles, with the excavation method selected and adjusted according to the actual geological conditions.
Depending on the ground conditions and project requirements, excavation may involve mechanised equipment in soft ground or drilling and blasting in hard rock. After each excavation step, support measures such as shotcrete, rock bolts and other ground reinforcement systems are implemented to stabilize the surrounding ground and ensure construction safety.
What is underground mining?
Underground mining is a method of extracting minerals below ground through a system of tunnels, mine workings and underground spaces.
In this environment, alongside the need for ground stability and safety, operational efficiency depends heavily on short construction cycles, rapid re-entry to the working face, and overall process reliability.
When geological conditions change, solutions must adapt
Conventional tunnelling and mining projects are directly exposed to real-world geological conditions. Every variation can impact ground stability, support quality, safety, advance cycles, and overall construction efficiency.
Ground conditions can shift continuously along the tunnel alignment, from soft ground to hard rock. These variations require excavation methods and support systems to adapt flexibly to maintain safe and stable operations.
After each excavation step, the stress state of the surrounding ground changes, directly affecting the stability of the working area. Timely support and reinforcement are essential to control risks and ensure safety during excavation.
Groundwater entering through fractures, weak zones, or unsealed areas can complicate construction and affect structural stability. Prompt water control and sealing using tailored injection solutions are critical.
Unexpected fissures, cavities, or geological anomalies may be encountered during excavation. If left unaddressed, they can affect support performance, ground reinforcement, and long-term structural durability.
Particularly in mining, every minute of downtime impacts productivity. Construction materials must achieve rapid early strength development to minimise waiting times and allow safe, rapid re-entry to the working face.
The Challenge: How can excavation, support, and ground reinforcement be executed safely, rapidly, and in a controlled manner when underground conditions are constantly changing?
Specialised solutions from MC Underground (MCU)
Shotcrete
Shotcrete plays a critical role in supporting and stabilising the surrounding ground after excavation, while also contributing to the long-term durability of the tunnel structure.
MCU provides:
- Alkali-free accelerators
- PCE superplasticisers
- Hydration control admixtures
- Rebound control agents
- PP macro & micro structural reinforcing fibres
These solutions help control both early-age and final strength development, support safe advance cycles, and reduce material losses caused by shotcrete rebound.
Rock bolting & Ground anchoring
Rock bolting and ground anchoring are key components of the support system, helping reinforce and stabilize the surrounding ground during tunnelling and mining operations.
MCU provides:
- Non-shrink anchor grouts
- Thixotropic anchor grouts
- Grout performance-enhancing admixtures
- Expansion-control admixtures
- Fast-curing PUS anchoring resins
These solutions are designed to provide reliable anchorage, efficient installation, and long-term performance of the ground support system.
Ground injection & Water control
Water ingress, fractures and unstable ground conditions can significantly affect the safety and progress of underground construction.
MCU provides:
- PU resins
- PUS resins
- Acrylate gels
- Rigid foaming resin systems
These specialised injection solutions help stabilise the ground, seal fractures and control water ingress, supporting safe and stable construction conditions.
Waterproofing & Surface protection
Underground structures are constantly exposed to water, moisture and environmental influences, placing high demands on waterproofing performance and long-term structural protection.
MCU provides:
- Spray-applied waterproofing membranes
- PVC waterproofing membranes
- Structural repair mortars
- Reprofiling mortars
- Protective coating systems
These solutions help control water ingress, restore surfaces and protect structures, contributing to the long-term durability of underground construction.
Cemented paste backfilling
In mining, backfilling post-excavation voids with cemented paste helps support ground stability while also improving the utilisation of mining waste.
MCU provides:
- Specialised plasticising admixtures
- Rheology-modifying admixtures
- Binder system optimisation solutions
These solutions improve pumpability and workability, optimise binder consumption, and enhance the efficiency of backfill material utilisation.
On-site & Technical support
The effectiveness of an underground construction solution depends not only on the materials themselves, but also on the ability to adjust and control the solution under actual site conditions.
MCU provides:
- Project-specific formulation development and adjustments
- On-site technical training
- EFNARC-supported training and certification
- Equipment calibration
MCU’s technical team works alongside project teams to optimize solutions, control quality, and enhance reliability throughout construction.
What sets MC Underground apart?
International team of experts
With more than 60 years of experience, MCU brings in-depth expertise in tunnelling and mining to projects worldwide.
Advanced technologies
Specialised material solutions developed to meet the specific technical requirements of underground construction.
Integrated system solutions
Integrated solutions covering shotcrete, rock bolting, ground injection, waterproofing, repair, reinforcement and structural protection.
Flexibility for every project
Solutions are flexibly adapted to the geological conditions, construction methods and specific technical requirements of each project.
24/7 technical support
The technical team supports projects throughout the entire process, from consultancy and training to on-site implementation and quality control.
NEWS & ACTIVITIES
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