Three-dimensional numerical analysis of the rock-cutting behavior of a disc cutter using particle flow code

The Linear Cutting Machine (LCM) test is one of the most powerful and reliable methods for verification of the design of disc cutters and predicting the Tunnel Boring Machine (TBM) performance. It has the advantages of predicting the actual load on the disc cutter from a laboratory test on actual-sized large rock samples. However, it also has the disadvantage of requiring large rock samples to be transported and/or prepared, involving extra cost. To overcome this problem, numerical modeling can be used to expand on the result of full scale cutting tests to evaluate the potential performance of various disc cutter types and cutting geometries for optimization purposes. In this study, PFC3D has been adopted for numerical analysis of the optimum cutter spacing and failure aspects of Korean Busan tuff. The results were compared with the results of LCM testing and numerical simulations using the finite element method. The optimum cutter spacing deduced from numerical simulations is in good agreement with the results of these methods. Consequently, it was shown that PFC3D can easily represent macroscopic rock specimens containing micro cracks.