TBM Disc Cutter Model Based on Admissible Energy Principles

Abstract

Disc cutters are the most critical tool for excavation by tunnel boring machine (TBM). Based on the energy conservation law, finite-element modeling, and elastic–plastic continuum theory for tunneling by TBM, the interaction between disc cutters and rock mass was examined. First, the disc cutter motion was studied to establish the disc cutter strain equations as a function of time. Second, by using elastic–plastic theory, a rock strain model was constructed. Finally, a three-directional force model with time-varying characteristics was established for disc cutters during rock breaking. The model was applied to the Qinling Mountains Tunnel of the Lan-Yu Railway. Model cutterhead thrust and torque values were found in good agreement with actual data. In brief, the model can be used to predict the TBM performance and examine the mechanism of rock breaking.