Thin spray-on liner (TSL) is a surface protection technology used by spraying a polymer film, which is widely used for mine airtightness and waterproofing. A reinforcing TSL can replace steel mesh, which is a new method for roadway support. This paper reviews the development of a reinforcing TSL. Considering the deterioration of geological conditions in deep underground mining and the demand for reinforcing automation, two kinds of polymeric reinforcing TSL (RPTSL) materials are developed. The mechanical characteristics of the new TSL materials are studied experimentally. Results show that the average compressive strength, tensile strength, cohesion, and internal friction angle of the two TSL materials are 52 and 32 MPa, 12 and 8 MPa, 6.2 and 17.2 MPa, and 33.6° and 25.9°, respectively. The bonding strength between the two materials and coal is greater than the tensile strength of coal itself, and the mechanical properties of the material for comparison are lower than those of both materials. Based on the TSL support mechanism, we examine the application of the two TSL materials to the mining environment and compare the mechanical properties of polymer materials and cement-based materials. The advantages of polymer materials include versatile mechanical properties, good adhesion, and high early strength. This study provides a new support material to replace steel mesh for roadway surface support, which satisfies the needs of different surface support designs under complex geological conditions, and promotes the automation of roadway support.

Rock burst is one major threat to mining safety and economy. Rock burst occurring in the longwall mining roadway accounts for 85% of the total amount of burst events. This paper investigates the causality mechanism of rock burst in longwall roadways by establishing a finite elastic beam model in the working face based on the elastic foundation theory. The breakage process of the main roof and related dynamic effects are analysed. The result shows that the movement of the main roof shows free vibration under certain damping resistance. It is also found that the roof dominant vibration frequency increases with the increase in the thickness and elastic modulus of the roof. During roof vibration, the vertical stress applied on the coal mass is unloaded. The destressing of the roof‐coal interface causes the coal mass in the roadway rib to slip into the roadway under the horizontal ground stress, resulting in rock burst. The possibility of rock burst increases with increase in the strength and thickness of the roof and horizontal ground stress within the coal mass. This mechanism explains the occurrence of rock burst in the mining roadway; it provides the fundamental theory for the prevention and controlling technologies of longwall roadway rock burst.

With increasing coal mining depth, coal bumps—disasters that severely compromise mine safety—have garnered growing attention in the mining industry. Among these, coal bump sliding-type coal bumps cause significant structural damage and pose serious safety hazards. Analysis of damage patterns indicates that such sliding typically originates from insufficient strength at the coal-rock interface. To address this issue, bolt support technology has been proposed to enhance the reinforcing capacity of roadway support systems at this critical interface. The arrangement angle of the bolts significantly affects the reinforcement of the interface. This study uses ABAQUS software to simulate and analyze the stress-strain and bearing characteristics of bolts at support angles of 30°, 45°, 60°, and 90°. The simulation results show that at support angles of 30° and 45°, the bolt fails primarily due to tensile forces, while at 60° and 90°, failure is mainly caused by shear forces. The higher load-carrying capacity of the bolt under tensile damage, compared to shear damage, indicates stronger reinforcement of the interfaces. The research findings were implemented in the return airway of a working face at a coal mine. Field observations during roadway excavation in the test section revealed relatively minimal roof separation. Compared to the conventional support system, the cumulative sidewall displacement was reduced by 28.6% during excavation and by 51.9% after mining commenced, while roof separation remained consistently low. These results confirm that the proposed bolt support technology significantly improves control of the surrounding rock mass in roadways.

As coal mining extends deeper underground, the coal bump brings significant challenges to production safety. As a type of coal bump, the large-scale sliding coal bump of coal body is characterized by overall coal body movement, and the bolt support system is exhibits minimal or no damage. To counteract such geomechanical hazards, the roadway support system must be capable of absorbing energy and reinforcing the coal-rock interface. Critical to this technique is the angle optimization of the support system, as tests demonstrate that bearing capacity is significantly sensitive to the angle of support during interface reinforcement. In this paper, bolts are experimentally simulated using AZ31 magnesium alloy and 5052 aluminum alloy specimens with varying diameters. The failure modes and bearing capacities of bolts are compared at support angles of 30°, 45°, 60°, and 90°. The results show that specimens primarily fail due to tensile forces at support angles of 30° and 45°, while failure is due to shear forces at angles of 60° and 90°. The bearing capacity of specimens is significantly higher under tensile failure compared to shear failure, and energy absorption capacity improves with increasing diameter. The research findings have been applied to the support design of the return airway at the 7305 working face in Kongzhuang Coal Mine.

This study examines mining operations beneath extensive magmatic rock strata. Through an analysis of the distribution characteristics of magmatic rock, a theoretical framework was developed to investigate the distribution features of key strata above the working face. Additionally, similar material simulation tests were performed to analyze the movement and fracture patterns of rock strata above the coal seam during the mining process at the 10,414 working face. Concurrently, numerical simulation software was utilized to compare and analyze the stress distribution and evolution patterns at the edges of the goaf during the mining processes of multiple working faces in the 104 mining area. These findings were juxtaposed with calculations from analogous working faces lacking thick magmatic rock overburden. By integrating geological and mining data from the 104 mining area, this paper presents construction techniques and essential parameters for remedial measures, thereby facilitating the safe and efficient mining of the remaining working faces in the 104 mining area.

Coal bumps pose a significant threat to the safe operation of coal mines. This study examines the coal bumps incident at Tangshan Mine, focusing on the influences of various disaster-causing factors, including structural stress, rock mass impact tendencies, and support and bearing capacity. To facilitate the safe resumption of production at the 0250 working face, coal seam blasting and borehole pressure relief drilling were conducted to dissipate the accumulated elastic energy within the coal seam, thereby effectively mitigating the risk of bursting. Concurrently, the vibration and displacement of the roof were monitored. The relevant monitoring data indicate that roof activity remains within a controllable range, suggesting a relatively low likelihood of coal bump incidents.