This study investigates the influence of oil well anchoring on overburden stability in coal, oil, and gas co-mining areas, combining mechanical theory and numerical simulations to systematically analyze the mechanical characteristics. First, a mechanical model of oil well anchoring was developed by considering the coupled interaction between the wellbore cement sheath and the surrounding rock, and the relationship between oil well anchoring and changes in the friction angle, cohesion, compressive strength, and Young’s modulus of the surrounding rock. Subsequently, a three-dimensional numerical simulation using FLAC3D 7.0 was conducted to analyze stress redistribution, displacement field evolution, and plastic zone distribution around the oil wells under different burial depths. The results indicate that as the burial depth increases, the peak stress around the oil wells rises from 0.37 MPa to 2.24 MPa, the displacement influence range expands from 18 m to 43 m, and the plastic zone remains confined between 0.9 m and 1.6 m. No significant stress coupling effects are observed between the well groups. These findings demonstrate that the anchoring effect of oil wells effectively regulates the stratigraphic stress field, mitigates overburden deformation, and enhances wellbore stability in coal, oil, and gas co-mining areas, providing a crucial theoretical basis and engineering reference for enhancing overburden stability in coal–oil co-mining areas.

In geotechnical engineering, traditional anchor bolts often have problems such as an insufficient bearing capacity, their ease of loosening, and an unsatisfactory support effect under complex geological conditions (such as soft soil or broken surrounding rock), resulting in it being difficult to guarantee engineering stability. In order to solve these problems, this paper studies the supporting performance of a hollow grouting anchor with an umbrella-shaped expansion head with an expansion pipe. Through theoretical analysis, mechanical performance analysis, and experimental analysis, the supporting mechanisms and mechanical characteristics of a hollow grouting anchor with an umbrella-shaped expansion head are systematically discussed. The calculation formula for the maximum pull-out force of the umbrella-shaped expansion head is clarified, and the fixed range of the expansion body section in relation to the loose ring is quantified. Based on the analysis results, the structural parameters and material properties of the bolt were optimized, and the optimization effect was verified by numerical simulation. The results show that the optimized bolt has significantly improved the pull-out bearing capacity, shear resistance, and reinforcement effect on the soil. The maximum pull-out force of the umbrella-shaped expansion head can be increased by up to 35%, and the fixed range of the expansion body section can be expanded by 45%. The research provides an efficient and reliable support solution for geotechnical engineering fields, such as roadway engineering and tunnel engineering, which significantly improves the stability and safety of engineering under complex geological conditions. At the same time, it provides an important theoretical basis and practical reference for the design and construction of similar projects.

To address the limitations of traditional hardened concrete road surfaces in coal mine tunnels, which are prone to damage and entail high maintenance costs, this study proposes using modular concrete blocks composed of fly ash and coal gangue as an alternative to conventional materials. These blocks offer advantages including ease of construction and rapid, straightforward maintenance, while also facilitating the reuse of substantial quantities of solid waste, thereby mitigating resource wastage and environmental pollution. Initially, the mineral composition of the raw materials was analyzed, confirming that although the physical and chemical properties of Liangshui Well coal gangue are slightly inferior to those of natural crushed stone, they still meet the criteria for use as concrete aggregate. For concrete blocks incorporating 20% fly ash, the steam curing process was optimized with a recommended static curing period of 16–24 h, a temperature ramp-up rate of 20 °C/h, and a constant temperature of 50 °C maintained for 24 h to ensure optimal performance. Orthogonal experimental analysis revealed that fly ash content exerted the greatest influence on the compressive strength of concrete, followed by the additional water content, whereas the aggregate particle size had a comparatively minor effect. The optimal mix proportion was identified as 20% fly ash content, a maximum aggregate size of 20 mm, and an additional water content of 70%. Performance testing indicated that the fabricated blocks exhibited a compressive strength of 32.1 MPa and a tensile strength of 2.93 MPa, with strong resistance to hydrolysis and sulfate attack, rendering them suitable for deployment in weakly alkaline underground environments. Considering the site-specific conditions of the Liangshuijing coal mine, ANSYS 2020 was employed to simulate and analyze the mechanical behavior of the blocks under varying loads, thicknesses, and dynamic conditions. The findings suggest that hexagonal coal gangue blocks with a side length of 20 cm and a thickness of 16 cm meet the structural requirements of most underground mine tunnels, offering a reference model for cost-effective paving and efficient roadway maintenance in coal mines.

Aiming at the problems of the complex in situ stress measurement process, difficult measurement and long-term monitoring, it is particularly important to design a three-dimensional borehole full stress monitoring method based on the principle of rock mass rheological stress recovery, which lays a foundation for underground construction, such as roadway engineering and tunnel engineering. Through theoretical calculation and mechanical analysis, the magnitude, direction and inclination of the stress at any point in the borehole of the geological body are analyzed. Based on this, a three-dimensional borehole full stress monitor is constructed. At the same time, the rheological stress change process of rock mass around the borehole is analyzed by numerical simulation, the rationality of the three-dimensional borehole full stress monitor is determined, and a new method of borehole surrounding rock stress monitoring is proposed. The results show that: (1) the stress monitoring of the surrounding rock can be realized by the stress recovery principle of a rock mass rheological borehole, and it can be monitored for a long time; (2) the three-dimensional borehole total stress monitor can reflect the size and direction of the six principal stresses of the surrounding rock stress through eight measuring points; (3) the design structure and mechanical properties of the three-dimensional borehole full stress monitor are reasonable, and the linearity and sensitivity of the hydraulic membrane material are reasonable, which can meet the standards of long-term monitoring.