In order to alleviate the relationship between mining and roadway, the 3204 working face and the 3206 roadway in Shanxi Taitou coal mine are taken as an example, and the width of mining and the support parameters of mining while reversing mining and excavation under dynamic pressure are optimized. The research includes field investigations, theoretical analysis, numerical simulation, and field tests. Based on the characteristics of roof fracture and the distribution of coal pillar stresses that determine the coal pillar is 18.7m wide, the control scheme of mining while reversing mining and excavation was developed; the stress of coal pillar and the characteristics of roadway deformation and failure are summarized. By means of FLAC^3D numerical simulation software, the influence of coal pillar widths and different mining positions on the stability of roadway surrounding rock are discussed. The asymmetric support structure of trapezoidal roadway is proposed as the core support, and the support scheme of dense bolts and anchor cables is proposed. The support of the 3206 return airway is composed of bolt, anchor cable, and anchor mesh, combined with M-shaped steel belt and steel beam. Through the research on the current situation of roadway support, the support scheme is optimized to make the 3206 return airway meet the production requirements, which provides a new breakthrough for roadway support under dynamic pressure in deep mines in China.

Based on the engineering background of providing advance support for the working face of mining roadways, this paper studies the reasonable support technology of advance roadway roofs by combining theoretical analysis, numerical simulation, and field tests. Based on the geological conditions of the 1304 working face of Yineng Coal Mine, the FLAC3D numerical simulation software was used to compare and analyze the effects of the original single hydraulic prop advance support and the bolt-mesh-cable support without the single hydraulic prop. The results show that although the deformation of the surrounding rock is reduced under the support of the single hydraulic prop, the convergence of the roof and floor of the roadway and the left and right sides are still as high as 288 mm and 308 mm, respectively, which does not meet the requirements for safe production. Based on this problem, this study proposes full-stress anchoring technology. FLAC3D numerical simulation software is used to simulate and analyze the supporting effect of the full-stress anchoring support technology in advanced mining roadways. The results of numerical simulation experiments show that the convergence of the roof and floor and the convergence of the left and right sides of the roadway surrounding rock are 33 mm and 52 mm, respectively, which have a good control effect on the roadway surrounding rock. The field test of bolt full-stress anchoring support technology was carried out in the return air roadway of the 1304 working face. The deformation of the surrounding rock of the roadway was monitored by setting up stations. The measured results show that the maximum roof and floor convergence of the roadway is 42 mm, and the maximum convergence of the two sides of the roadway is 69 mm, which meets the requirements for safe mining on site. In this study, by comparing with the advance support effect of the original single hydraulic prop, the rationality of the full-stress anchoring technology of the mining roadway in the advance section of the working panel is determined. The use of bolt full-stress anchoring instead of the traditional single hydraulic prop for advanced support has a better surrounding rock control effect and a lower support cost. This is a new technology for advanced support of surrounding rock in mining roadways, which enriches the control technology of roadway surrounding rock and also provides technical reference for other similar engineering cases.

Background: Coal mining requires safe and effective roadway support to ensure production and worker safety. Anchor support is a common method used for controlling the roof of coal seams. This study aims to analyze the effectiveness of different anchor support schemes and provide a theoretical basis for designing safe and effective roadway support. Methods: The authors used a computer simulation tool called FLAC3D to simulate and analyze the spacing between anchor bolts, anchor bolt length, anchor cable length, and effective roadway roof control, and support the schemes at the western wing roadway in the no. 15 coal seam of no. 1 mine of Ping’an Coal Mine. Results: The study found that using different combinations of anchor bolts and cables with varying lengths could effectively control the deformation of the roadway surrounding rock, depending on the spacing between layers of the coal seam. The most effective support schemes were recommended depending on the specific conditions. Conclusion: The study provides a theoretical basis for the design of anchor support in coal mines, which can ensure the safety of production and improve roadway stability. The results could be useful for other mining operations facing similar challenges in roadway support and stability.

The coal mining industry in Pakistan faces recurring fatal accidents due to data scarcity, lack of research, and technology adoption. This paper reviews the current status of coal mining, the ongoing energy crisis, the utilization of indigenous coal resources, and the prevailing safety challenges. By comparing coal mining safety standards in Pakistan with global benchmarks, this study proposes advanced mining technologies to improve productivity and safety. This study emphasizes the importance of investigating the underlying factors causing mining accidents in order to devise effective strategies to mitigate them. The lack of relevant data and the reluctance to adopt technology in the industry are identified as major obstacles to improving safety conditions. The proposed strategies for overcoming safety issues include improving data collection and analysis, increasing research efforts, and promoting the adoption of advanced technology. Thus, this paper highlights the urgent need to address safety concerns in Pakistan’s coal mining industry to avoid further loss of lives and resources.

Studies have confirmed the poor stability of layered roofs with weak interlayers, and it is necessary to study the roof-caving mechanism of such roadways. A model of a weak interlayer was established to study the influence of the layer position and horizontal stress of layered roofs with weak interlayers on the stability of roadway roofs. FLAC^3D numerical simulation software was used to study the damage characteristics of weak interlayers and different horizontal stresses on roadway roofs. Based on Proctor’s theory, a maximum caving arch model was proposed to obtain the maximum caving arch height and span range. The pressure measurement coefficient and the vertical displacement change of the roof strata conformed to corresponding linear functions by fitting the pressure measurement coefficient and the maximum vertical displacement. A bolt-while-drilling support method (BWD) was proposed based on team measurement-while-drilling (MWD) to accurately determine the location of weak rock layers and the development range of plastic zones. A maximum caving arch model was proposed to obtain the range of influence of the maximum caving arch and the range of the maximum slope collapse angle. Furthermore, a method of anchor rod support-while-drilling was proposed and tested on-site in Jingu Coal Industry, Guxian County, Shanxi Province, China. According to the site conditions, short anchor cables were used to pass through the weak interlayer of roofs, with a good support effect. The results provide a new method for layered roof support containing weak interlayers.

Coal-accompanying gas is an essential resource, with numerous mining methods. The practice has proved that injecting high-pressure air into the coal seam can replace and flush the gas in the coal seam, effectively solving the problem of inadequate single gas drainage in soft and low permeability coal seams. This paper uses the finite element method to solve the model, simulate and study the gas drainage by high-pressure air injection in the bedding drilling, and establish a fluid-structure coupling model for gas drainage by high-pressure air injection. The competitive adsorption of N₂, O₂, and CH₄, diffusion and migration of CH₄ in coal matrix and fissure, matrix deformation caused by CH₄ adsorption, and desorption and control of coal deformation by applied stress are considered in the model. When the fixed extraction time is 600 days (d), the optimal spacing between the extraction hole and injection hole is 12.5 m. The safe extraction effect and minimum drilling amount can be ensured. It provides a basis for guiding gas drainage by injecting high-pressure air on-site.