## 1 Introduction
To simulate the entire rock fragmentation process, discontinuous medium analysis methods are needed. In this context, [PERSON] et al. [10] employed the Discontinuous Deformation Analysis (DDA) program to simulate tunnel excavation blasting. [PERSON] et al. [11] used a coupled FEM and discrete element method (DEM) model for bench blasting in deep tunnels. [PERSON] et al. [12] combining finite and discrete element methods, investigated the effects of mineral particle composition and size on the macroscopic blasting pattern of rocks by studying the micromechanical properties of rock mineral particles. [PERSON] et al. [13] developed a coupled model of Smoothed Particle Hydrodynamics (SPH) and the FEM to study damage and crack patterns in rock blasting. Moreover, the Universal Distinct Element Code (UDEC) program [14] and the Particle Flow Code (PFC) [15] are also capable of simulating the rock blasting process. Smoothed Particle Hydrodynamics (SPH) is a numerical method that integrates mesh-free techniques, Lagrangian methods, and particle flow methods. This approach uses particle-like elements to carry mechanical quantities, tracking their motion and accurately obtaining corresponding mechanical information through specific mathematical relationships. Due to algorithmic differences, the SPH method requires strict computational conditions and extended time compared with traditional finite element methods. It also has shortcomings in addressing boundary conditions. Therefore, to comprehensively and accurately simulate the blasting impact process, an SPH-FEM method is proposed, which employs the SPH method in the near field and the finite element method in the far field. In the numerical simulation of rock blasting processes, the SPH-FEM coupling method combines the advantages of both approaches. SPH is used to simulate rock fragmentation and large deformations, while the conventional FEM ensures stability and efficiency in the far field of the blast. At the coupling interface, SPH particles and finite elements transfer mechanical information of the same material through solid contact, ensuring displacement coordination between the two via a point-to-surface bonding approach. Additionally, this method can fully utilize finite element boundary constraint methods to accurately analyze specific issues such as rock blast damage, thereby improving computational efficiency. Given the wide application of the LS-DYNA (R14) program in blasting engineering and its integration of the SPH algorithm, it effectively simulates the throwing and collision of rock fragments post-blast. This study employs LS-DYNA software and the FEM-SPH coupling simulation method. The underground ore body of the Karatongk Mine in Xinjiang contains disseminated copper-nickel ore, primarily comprising mafic complex rocks that mostly exhibit a massive structure. Aside from the brecciated rock group, other ore groups display good stability, with the main structure of the ore rock being dense and hard, and the Protodyakonov coefficient (f) ranging between 8 and 10. The lithology is complex, consisting of rocks with massive structures such as norrite, gabbro-norite, diabase, and norrite. In addition to the mafic complex rocks, there are strata dominated by tufaceous limestone and intermediate to acidic dikes. The geological structure is well-developed, with frequent occurrences of fault crush zones within the rock mass, and it is situated in an area active with neotectonic movements. The blasting height of the ore rock is 4.5 m, with a width of 4.6 m and an advance of 2.3 m. A total of six rows of blast holes are arranged.