Blast Hole Drilling

Blast hole Drilling is a technique used in mining whereby a hole is drilled into the surface of the rock, packed with explosive material, and detonated. The aim of this technique is to induce cracks in the inner geology of the surrounding rock, in order to facilitate further drilling and associated mining activity.

Advantages

1. Drilling and blasting is a very versatile method that can be utilized in all different types of rocks.
2. Drill and blast requires a lower up-front investment than acquiring a TBM, making it a more economically friendly option.
3. Drilling and blasting is an environmentally friendly option that can significantly reduce noise, dust, and visual pollution, and instead isolates any pollution near the tunnel portal.
4. Compared to cut-and-cover, the quantity of construction & demolition materials (C&D) is greatly reduced.
5. Compared to cut-and-cover, disturbances to local traffic are greatly reduced.

Disadvantages

1. Since drill and blast involves the usage of explosives, there is the potential hazard associated with establishing a temporary storage site for said explosives, often called a magazine site. This potential hazard can be mitigated through the planning and site selection process.
2. Compared to TBM, drill and blast mining results in higher vibration levels.