## 1 Introduction
Under shear conditions, many scholars focused on the effects of anchors on shear force, displacement, and deformation, and achieved good results. In 2020, [PERSON] et al. [17] explored in detail the fracture and anchorage mechanisms of jointed rock bodies on a microscopic scale by using the digital speckle correlation method, acoustic emission technology, and X-ray CT observation. In 2021, [PERSON] et al. [18] conducted anchorage shear tests. It was identified that the residual resistance contribution of full-length bond bolts was the largest at anchorage angles of 55\({}^{\circ}\) to 70\({}^{\circ}\). The maximum contribution of the anchor bolts increased linearly with the increase in the joint extension angle. In addition, the effects of different anchorage types, anchorage patterns, joint roughness values, loading angles, and displacement angles were investigated in the anchorage shear tests. With the rapid development of computer technology, numerical simulation has gradually become one of the mainstream research methods in the field of rock mechanics [19; 20]. In the study of the mechanical behavior of anchored fractured rock, there are usually two methods, i.e., the finite element method (FEM) and discrete element method (DEM). [PERSON] et al. [21] utilized the finite element analysis software ANSYS 2013R2 to construct a finite element model of fractured rock anchorage, investigating the impact of rock fractures on the load transfer mechanism of anchoring. Through numerical calculations, they analyzed the effects of fracture aperture, fracture length, and fracture position on the stress transfer mechanism in the anchored fractures. [PERSON] et al. [22] analyzed the mechanism of \"S\"-type joint fractures in the fractured rock body and carried out numerical simulation research on the anchoring effect of this joint. They established the model of the fractured rock body under different anchoring methods using FEM software FLAC3D 5.0, and carried out simulation tests to analyze the mechanical properties of the fractured rock body under different anchoring methods. Comparison and analysis of the anchoring effect and the main damage mode under different anchoring methods. [PERSON] et al. [16] used the FEM software ABAQUS (2018) to carry out a series of numerical simulation studies on the mechanical properties and anchoring effect of prestressed anchors reinforcing the fissured rock mass. In summary, the internal monitoring values of the samples, as well as the deformation and stress of the anchors can be easily obtained using FEM; however, the microscopic changes inside the rock mass are difficult to capture. DEM can better capture some microscopic information inside the sample during the load damage process compared to FEM, and simulate the microcracks sprouting and expanding in the sample. Among them, many researchers have used bonded particles (BPs) in DEM to simulate anchors and rock masses [23]. [PERSON] et al. [24] used three-dimensional particle flow code (PFC3D) to investigate the effect of different anchorage angles on crack extensions from a microscopic point of view, and used BPs in PFC to simulate both the rock body and the anchor system. [PERSON] [25] conducted a series of numerical simulations using PFC3D to explore the mechanical impacts of anchoring on cracked rock. In these simulations, the rock mass was represented by the bonded particle model (BP) within PFC, while the prestressed anchor system was modeled using the Clump method. It is not difficult to find that the internal monitoring values of the samples, as well as the deformation and stress of the anchors, can be easily obtained using FEM. However, the microscopic changes inside the rock mass are difficult to be captured [26; 27; 28]. In contrast, DEM offers a distinct advantage over FEM in capturing microscopic details within a sample during the loading and damage process, effectively simulating the initiation and propagation of microcracks within the material [29; 30; 31].