## 6 Conclusions  
Through theoretical analysis, numerical simulation, and field monitoring, the vertical stress and strain energy density evolution rules of the knife handle working face were analyzed, the overlying rock fracture induction mechanism of the working face was revealed, and a hydraulic fracturing layer analysis method was proposed. On-site mine pressure data and microseismic data after hydraulic fracturing were analyzed. This study leads us to the following four conclusions:  
1. Based on the actual conditions of the working face, a mechanical model of the roof's periodic fracture thin plate was established for quantitative analysis, and a mechanical model of the roof with simple support on both sides and fixed support on both sides was determined. As the width of the working face increases, the load on the roof increases and the load of overlying strata is transferred to the coal in front of the working face. The coal inclines to the upper and lower sides of the working face. The high static load is caused by the lateral support pressure of the gob and the high dynamic load is caused by the large-area collapse of the roof; they are more likely to induce rock burst. 2. Through numerical simulation, the evolution and energy release rules of the advanced support pressure are revealed in the knife handle working face. The results show that when the working surface width increases from 85 m to 137.8 m, the peak value of the advanced supporting pressure of the working surface increases from 10.31 MPa to 14.62 MPa; the increase of support pressure is 4.31 MPa. The peak strain energy density of the working face increases from 1.21 \(\times\) 10\({}^{5}\) J/m\({}^{3}\) to 1.78 \(\times\) 10\({}^{5}\) J/m\({}^{3}\). As the width of the working face increases, the peak strain energy density shows an increasing trend, and the large energy area gradually increases when the working face advances. Figure 15: Energy/frequency comparison diagram of microseismic events. 3. In view of on-site impact risk factors such as higher energy concentration on the roof when the width of the working surface increases, and stronger dynamic load disturbance when the hard roof collapses, measures for advanced weakening of the hydraulic fracturing roof are proposed; the hydraulic fracturing layer is determined through the identification of key overlying rock layers and energy release layers. Support pressure and microseismic data are used to analyze the working face rockburst prevention and control plans. After using hydraulic fracturing technology, the working face roof pressure step distance was reduced, and the frequency of microseismic energy was significantly reduced, which reduced the risk of working face impact and ensured safe mining of the working face. 4. The testing of the hydraulic fracturing effect on the working face needs to be further studied and solved in actual situations. In addition to support pressure and microseismic signals, transient electromagnetic detection and borehole peeking are also often used to test the pressure relief effect. Different methods will be used in future research. Comparative analysis of fracturing effects can further improve the accuracy of monitoring results. In addition, microseismic events and acoustic emission events during the mining process can be analyzed in depth, impact risk evaluation indicators and discrimination criteria can be determined, and impact risk can be evaluated timely and accurately to ensure safe mining on the working face. [PERSON] conceived, designed, and analyzed the test results; [PERSON] performed the experiments and wrote the manuscript; [PERSON] use software; [PERSON] project administration; [PERSON] participate in the processing of some data. All authors have made equal contributions to the revision of the paper. All authors have read and agreed to the published version of the manuscript. This work was sponsored by the National Natural Science Foundation of China (No.