Effect of geometrical characteristics of TBM disc cutter on rock excavation: a focus on cutter diameter and cutter tip profile

Disc cutters are the most commonly used cutting tools in various types of tunnel boring machines (TBMs). Estimating the force required for cutting a specific type of rock using disc cutters is a crucial aspect of the TBM cutter head design and the prediction of TBM performance. In this study, various types of rocks are fractured by applying load through a disc cutter near the edge of cubic rock samples using a uniaxial compressive strength test apparatus. Regarding the geometrical configuration of TBM disc cutters, different cutter diameters and various cutter tip radii are used to determine the failure load for each rock type and to develop a machine learning prediction model. The results confirm that larger disc diameters and greater tip radii increase the failure load as high as 20% and more than 100%, respectively. Meanwhile, the profile used for the cutter tip is the most prominent parameter influencing the normal force leading to failure.