## 1 Introduction
In a grouting water plugging project, [PERSON] [18,25], installed part of the drainage pipe utilizing the field experiment method to draw the groundwater out of the grouting project, which effectively reduced a large amount of groundwater during the grouting process. The way in which to address the amount of grouting engineering groundwater presents new feasible ideas. Based on engineering examples, [PERSON] et al. [26], considered the problem of slurry solidification and verified the drainage design with experiments which effectively reduced the impact of groundwater on grouting. To determine the influence of groundwater on grouting, [PERSON] et al. [27], considered more factors of grouting pipes and the characteristics of underground water inflow, and proved that drainage is also an important means to ensure project safety. [PERSON] et al. [28], considered diverting grouting and optimizing the construction process. The results show that drainage is the best method for sustainable development when the water inflow is large. Scholars have found that these methods have two main advantages. For instance, large amounts of groundwater can be diverted, which can reduce pollution and hazards to engineering construction and avoid the problem of groundwater flowing out of tiny cracks in the grouting method of water blocking, which is conducive to the engineering environment and safety assurance. In addition, the drained groundwater can be stored for domestic purposes, such as hydroelectric power generation. This not only saves water resources and increases resource utilization but also enables better water resource management [29]. However, drainage is not easy, and drainage tubes and other equipment should not be arranged blindly. If the main part of the drainage pipe and other equipment are placed in a location with small groundwater flow, the location with a large flow of groundwater cannot effectively divert the groundwater; therefore, a large amount of groundwater will still gather there and the result will still cause groundwater pollution and harm. Therefore, it is necessary to rationally arrange drainage pipes and other equipment to efficiently divert groundwater [30]. The key to rationally arranging drainage pipes and other equipment is to clarify the pore structure characteristics of the rock and then grasp the flow characteristics of fluid seepage. In addition, most drainage engineering examples studied by scholars did not exceed a depth of 1000 m. The deep underground geological conditions below 1000 m (hereafter referred to as the deep) are complex, and the geological conditions of the shallow part are quite different. In other words, the fluid seepage characteristic at low depths cannot be directly used for reference in deep underground engineering. This further increases the difficulty of drainage operations in deep underground projects. Therefore, the characteristics of how the fluid seeps into the deep underground rock, where the flow is large, where the flow velocity is fast, and how these locations are distributed are all important to the drainage of groundwater. This manuscript aims to effectively divert groundwater, reduce groundwater hazards, reduce environmental pollution caused by groundwater, solve the pollution and safety hazards of groundwater influx to underground resource mining and other projects, and help clean the production of underground resource mining and other projects. At the same time, the use of water resources should be increased to contribute to the sustainable development of resources. We mainly explore the fluid seepage characteristic in deep underground rock and perform the following work. In this study, rock samples were obtained from the site of a deep underground project. And this research does not rely solely on engineering experience, but comprehensively uses various methods such as experiments, numerical simulations, and field verifications.