Predicting Performance of Raise Boring Machines Using Empirical Models

Excerpt

Raise boring machines are used for excavation of shafts and other vertical structures in mining and civil engineering fields for material, human transportation and ventilation purposes. RBM uses a small diameter drill rod, around 230–350 mm to drill a pilot hole down to the required depth. Once the pilot hole has been drilled to the desired depth, a reamer is attached to the drill rod. The reamer is then pulled back up to the upper level, creating a round shape. This continues operation provides a faster advance rate than other methods. The flexibility in different angles and diameters is a great advantage compared to drill and blast excavation method. RBM creates a shaft with smooth walls which usually does not require lining in an appropriate geology. The hole is more stable than a drilled and blasted method and has better air flow, making it ideal for ventilation shafts. …