## 1 Introduction
At present, a series of HJC model parameters of rocks or rock-like media have been determined, including limestone, granite porphyry, granite, sandstone, marble, and coal [24; 25; 26; 27; 28]. Scholars have performed research analysing the structural design and rock-breaking efficiency, and simulating the rock-breaking process of shield disc cutters. Regarding the structural design of disc cutters, [PERSON] et al. [29] found that changes in blade width had less effect on disc cutter wear. [PERSON] et al. [30] designed a parametric model of the variable cross-section (VCS) cutter ring and used FEM to simulate rolling behaviour, and the results showed that the VCS cutter ring applied a periodic force to the rocks during the rolling process. With regard to rock-breaking efficiency, [PERSON] [31] proposed the concept of specific energy, which is defined as the energy required to excavate a unit volume of rock. [PERSON] et al. [32] found that the spacing between disc cutters had a greater impact on specific energy than penetration, and a spacing of 76 mm was close to optimum in hard and brittle crystalline rock. [PERSON] et al. [33] carried out a full-scale cutting test for a 432 mm disc cutter with three different blade widths, and found that the specific energy and optimal spacing were positively related to blade width. Scholars have also performed a lot of work on the numerical simulation of rock-breaking using shield disc cutters. [PERSON] et al. [34] used AUTODYN-3D to simulate the three-dimensional dynamic failure observed in LCM tests and determined the optimum cutter spacing by calculating the specific energy. [PERSON] et al. [35] built a model of a disc cutter by Pro/E and carried out a numerical simulation of rock-breaking using the disc cutter. The results showed that the disc cutter was able to cut hard rock, and the contact force was in agreement with the common prediction formula for disc cutter forces, which showed that the modelling method was correct and feasible. [PERSON] et al. [36] established five rock-breaking models for disc cutters with different diameters and penetrations, and found that with increasing disc cutter diameter and penetration,the contact force increased as well. [PERSON] et al. [37] implemented a numerical simulation of the optimum cutter spacing and failure aspects of Korean tuff, and the results were compared with those of the LCM test, showing that the numerical method was correct. [PERSON] et al. [38] created a numerical model that combined the advantages of DEM and FEM to more accurately simulate the rock-breaking process of a disc cutter. [PERSON] et al. [39] developed a general particle dynamics code to simulate the rock-breaking process of a disc cutter in the mixed-face ground, and a novel algorithm of the contacts at the boundary between the two different media was proposed. By investigating existing studies, it can be found that the existing research on the structural design and numerical simulation of disc cutters is not specific enough, and only describes the general influence of geometric configuration on the rock-breaking behaviour of the disc cutter, without further considering the influence of geometric configuration. This paper aims to explore the influence of the geometric configuration of the disc cutter on the rock-breaking process and to provide guidance for the design and selection of the geometric configuration of the disc cutter. Section 1 introduces the currently existing research and provides a brief introduction to the work carried out in this paper. In Section 2, a comprehensive introduction to the HJC model is provided, including the strength equation, state equation, and damage equation. To ensure the accuracy of the numerical simulation, Section 3 introduces a method for determining the parameters of the diorite HJC model in the Jinan area, and uses the uniaxial compression test, triaxial compression test, Brazilian splitting test and split Hopkinson compression bar test to determine the parameters of the HJC model in the Jinan area.