Challenges and opportunities of using tunnel boring machines in mining

Full-face tunnel boring machine (TBM) tunnelling has unparalleled advantages over conventional drill-and-blast (D&B) techniques in terms of higher advance rates and lower risk levels in favourable ground conditions. However, there are only a few successful TBM applications in mines. The aim of this paper is to discuss the technical challenges of using TBMs in mining since the pioneering work in the 1960s. It starts with a description on the genesis of hard rock mines and coal mines and the differences of TBM tunnelling in mining and civil engineering projects. The historical applications of TBMs in mines are critically reviewed and the reasons for the unsuccessful applications are summarised and analysed from a geological point of view. Challenges, such as cutter wear, jamming and steering difficulties in difficult grounds with water inrush, fractured and faulted zones, high in-situ stresses, and gas, are explored in depth through case histories. Moreover, the corresponding mitigations measures to cope with complex grounds in mines are provided. A prospect of TBM applications in mining is presented at the end.