During construction, we manage the balance between minimizing project time and assuring uninterrupted operations in the future.
The way we achieve this is through the
- use of proven methods, materials and systems
- use of state of the art technology and the most modern equipment available
Our stringent quality control helps to reduce the risk of down-time during the lifetime of the shaft.
Drill and Blast Shaft Sinking
We build all kinds of vertical, inclined or horizontal mine openings using the conventional drill and blast technique. In the Drill & Blast method we:
- Secure the floor, drill blast holes, place charges and detonators in those holes and then execute ignition
- We then remove the spoil, secure the opening and repeat the process until we reach the desired depth
Shaftsinking with Ground Freezing
Redpath Deilmann is one of the leading firms in ground freezing.
Ground freezing is used when we face water-bearing ground conditions and/or weak rock, for example quick sand.
- The technique consists of developing a wall of frozen soil around the shaft, which prevents the ingress of water and stabilizes the ground. To achieve this, we drill vertical holes surrounding the shaft, circulate a cooling agent in the casing, which results in freezing of the surrounding soil
- Once the ground is frozen, the ground properties are similar to those competent rock, which enables us to sink the shaft using conventional drill and blast technique
- Subsequently a waterproof shaft liner is installed
Shaftsinking with Grouting
Grouting is another ground stabilizing or geotechnical reinforcement technique used when faced with water-bearing but stable ground.
- Step by step, holes are drilled and cement is injected into the ground, creating a sealing ring around the shaft
- This part of the shaft is then secured with a waterproof composite liner or cast iron tubbings