Numerical Simulation of Rock Fragmentation with TBM Disc Cutter in Linear Cutting Test

Summary This study is to simulate the rock fragmentation process with disc cutter in linear cutting machine (LCM) using the numerical method of finite element. The numerical model of rock and disc cutter was built according to the experimental settings, and then, validated with the test data. The rock model was built for Indiana Limestone as it was used in experimental study. The comparison of cutting forces obtained from the numerical simulation with those obtained from LCM test showed a good agreement between the simulation and the test results.
Introduction Use of tunnel boring machine (TBM) for hard rock tunneling has been ever increased due to the growth of technology and society, as well as growing demand. The main role of disc cutters in this machine is rock cutting. An accurate estimation of the forces acting on the disc cutter is very important in machine design. To do so, the cutting forces acting on a single disc cutter as well as its performance in a specific rock are predicted using full-scale linear rock cutting tests. The results are then generalized for TBM design in the same rock.
Methodology and Approaches The commercial finite element code ABAQUS/CAE was used to perform the numerical simulations of the rock cutting process in LCM test. The forces acting on a fresh constant cross section disc and specific energy were simulated. For validation purposes, the results obtained from numerical model were compared with those of experimental results.
Results and Conclusions The model validity was checked by comparing the results recorded from the experiments and those results obtained from numerical simulation. All cutting forces obtained from simulation were located in the confidence interval of experimental data. The analysis results showed that cutting forces and cutting coefficient increased non-linearly with increasing disc penetration. A good agreement was obtained between the numerical results and experimental data. Moreover, the cutting forces obtained from the simulation showed a maximum deviation of 15 and 21% from the experimental average values for normal force in penetration depth of 5 mm and rolling force in 2.5 mm, respectively.