Study on abrasivity characteristics of surrounding rock in long inclined-shaft of coal mine by TBM techniques

The abrasivity of surrounding rocks is one of the most important characteristics for the estimation of tool wearing. Itis often described through Cerchar Abrasivity Index (CAI). Based on long inclined-shaft of coalmine excavation by (Tunnel Boring Machine) TBM techniques, CAI and mineral composition are determined by Cerchar abrasivity test and X-Ray diffraction test, abrasivity classification and the relationship between mineral composition and CAI are analyzed. The results turned out that rock samples sampling from construction area mainly consist of quartz, potassium feldspar, anorthose, calcite, pyrite and clay mineral. There is a close linear correlation between CAI and equivalent quartz content. In long inclined-shaft, surrounding rock is slightly and medium abrasive, selection of tools based on CAI and mineral composition is feasible. Therefore it is helpful to combined tests results with practical situation to study the tools selection and reasonable distance of tools changing.