Impact of Rock Abrasivity on TBM Cutter-Discs During Tunnelling in Various Rock Formations

Abstract

With the introduction of tunnel boring machines (TBMs), the rate of development and construction of tunnels has increased across the world. Breakdowns, repairs and replacements that occur in a TBM have to be addressed within the tunnel. Of the several components within a TBM, the cutter-picks within the cutter-head undergo maximum wear and tear, thereby requiring periodic replacements. In order to optimize the consumption of cutter-picks, it is important to analyse the forces involved in the cutter and the properties that govern rock–cutter interactions. One such property is the abrasivity, which can be determined by CERCHAR abrasivity index (CAI) tests. Research suggests that the value of CAI is largely dependent on the mineralogical, physical and mechanical properties of rocks. Therefore, this study aims to perform experimental analysis of the various properties and their corresponding effects on granite and to determine the respective changes in CAI.