The intellectualization of coal mines provides core technical support for the high-quality development of the coal industry. Intelligent texts, especially intelligent policy documents, play an extremely important role in analyzing the trend of intelligent policies in coal mines. This paper collects more than 50 central and local intelligent coal mine policy texts from recent years. The method of text analysis is a tool used for text mining, and semantic networks are generated; it reflects that the policy mainly focuses on promoting large-scale equipment and platform integration, to promote the overall goal of safe, efficient, and intelligent development of coal mining. By analyzing the high-frequency words of the policy from 2016 to 2022, it reflects that the policy trend mainly goes through the following three stages: firstly, eliminate backward enterprises, encourage coal mine automation and mechanization; then, standardize the basic concept of coal mine intellectualization, carry out the transformation of coal mine intellectualization; and the third stage is to promote the application of key technologies of intellectualization, build intelligent demonstration coal mines and reach the acceptance stage, and promote the further development trend of coal mine intellectualization.

As an important technology of thick coal seam mining, fully mechanized mining with a large mining height has high mining efficiency. In order to study the roof safety control of large mining height working face, the 122106 working face of Caojiatan coal mine is taken as the engineering background. The numerical simulation method is used to analyze the control ability of roof subsidence when the support strength is 1.2 MPa, 1.4 MPa, 1.6 MPa, 1.8 MPa, 2.0 MPa, and 2.2 MPa. The results show that the support strength of hydraulic support is negatively correlated with roof subsidence. Through theoretical analysis of the mechanical model of the support and surrounding rock under the filling condition, it is shown that the height of the gap between the filling body and roof is the main influencing factor of roof subsidence: the smaller the height of the gap between the filling body and roof, the better the control effect on the roof. Through numerical simulation, the roof subsidence and surface subsidence under different filling rates are analyzed. The results show that when the filling rate increases to 80% the control of roof subsidence achieves better results. Taking production safety and economic benefits into consideration, when the reasonable support strength of the working face is determined to be 2.0 MPa and the filling rate is 80%, the safety control of the working face roof can be ensured.

Aiming at the serious deformation and failure of mining roadway under the condition of high secondary stress in Xuchang Coal Mine, Shandong Province, the deformation law of surrounding rock under the influence of high secondary stress in the original support belt transport roadway was analyzed by the method of field measurement and numerical simulation, and the control scheme of surrounding rock was put forward. According to the actual site conditions of 3318 working face belt transport drift in Xuchang Coal Mine, this paper proposed a new bolt-net support technology scheme with high strength, high stiffness, and asymmetric characteristics and obtained through numerical simulation analysis: (1) when the 3318 working face begins to mining, the distribution of the maximum principal stress in the surrounding rock of the roadway changes from weak symmetry to strong asymmetry, especially the maximum principal stress in the surrounding rock of the two sides; (2) the superposition effect of leading abutment pressure, lateral abutment pressure, and fault structure has a strong influence on the distribution of the maximum principal stress of roadway surrounding rock. The field industrial test shows that the deformation of the surrounding rock at different parts of the belt transport roadway is significantly reduced after the implementation of the double-height asymmetric bolting support. Among them, the deformation of the roof decreases from 630 mm to 185 mm, the deformation of the left wall decreases from 550~620 mm to 150~170 mm, and the deformation of the right wall decreases from 600 mm to less than 180 mm. The nonuniform deformation degree of the top side is within 1~1.13, indicating that the anchor mesh composite bearing structure is uniformly deformed as a whole, and the overall bearing capacity of the structure is realized.

Solid waste filling and roadway retaining can effectively control surface subsidence and alleviate solid waste accumulation pollution. In order to effectively evaluate the advantages of solid waste filling in deformation control of overlying strata and surrounding rock of retained roadways, this study used theoretical analysis and numerical simulation methods to analyze the factors affecting surface subsidence, as well as the deformation characteristics of surrounding rocks and retaining tunnels during backfill mining. By calculating the influence of factors such as the foundation coefficient and the filling rate on the subsidence of the roof, it is concluded that the filling rate is the main controlling factor affecting the subsidence of the roof. Through simulation and comprehensive analysis of the impact of different filling rates on overlying rock migration, it was found that when the filling rates are 70 % and 80 %, it can effectively control the subsidence of overlying rock in the mining area. By simulating the effects of these two filling rate conditions on the deformation of surrounding rock within the retained roadway zone, the results show that the optimal filling rate that can effectively control the subsidence of the overlying rock and improve the stability of the retained roadway is 80 %.