In view of the problems of composite roof coal roadway under multiple dynamic pressure disturbances such as strong stratification, large deformation of the roadway surrounding rock, and poor safety and reliability, this paper analyzed the deformation and instability characteristics of composite roof coal roadway under different influencing factors using numerical simulation and expounded the stress distribution pattern of composite roof coal roadway under multiple dynamic pressure disturbances. The geological conditions of gas control roadway in the 22301 working face of Tunlan coal mine are taken as examples, and this study is carried out based on the analysis of roof instability conditions of composite roof coal roadway. The progressive crack development characteristics in composite roof coal roadway and the instability failure mode of surrounding rock under multiple dynamic pressure disturbances were revealed, and the control mechanism and support scheme were put forward. According to the result, it is difficult to form a stable bearing rock beam due to the occurrence characteristics of the weak interlayer of the composite roof. The deflection of the roadway roof and the extent of the plastic zone are negatively correlated with the distance from the soft rock layer to the roadway but positively correlated with the thickness of the soft rock layer. As the lateral pressure coefficient increases, the plastic zone of the roadway surrounding rock first decreases and then increases. With the increasing influence of dynamic pressure, the coal roadway with composite roof suffers from greater damage under the superposition of high ground stress, lateral abutment pressure, and advance abutment pressure, which is characterized by significant zonal failure of the roof and asymmetric failure of surrounding rock. The control method of high-strength thick can construct the thick layer stable rock beam of the roof and equivalent support of the side, realizing continuous stress transfer and geometrically coordinated deformation. The support scheme was finally applied to the on-site industrial test, and the mine pressure monitoring results showed that the deformation of the roadway surrounding rock was effectively controlled under the new support scheme.

A floor rock roadway under an oblique straddle working face is a typical dynamic pressure roadway. Under the complex disturbance of excavation engineering works, the roadway often undergoes stress concentration and severe deformation and damage. To solve the problem of surrounding rock stability control for this roadway type, this study considered the East Forth main transport roadway in the floor strata of the 1762(3) working face of the Pansan coal mine. In situ ground pressure monitoring and numerical simulation calculation using the FLAC2D software were carried out. The influence laws of the surrounding rock lithology, the vertical and horizontal distance between the roadway and overlying working face, the positional relationship between the roadway and the overlying working face, and the support form and strength of the rock surrounding an oblique straddle roadway were obtained. Within the range of mining influence, the properties of the rock surrounding the roof and floor were very different, and the deformation of the rock surrounding the two sides exhibited regional difference. The influence range of the mining working face on the rock floor of the roadway was approximately 30–40 m, and that of horizontal mining was approximately 50–60 m. The mining influence on the rock surrounding the side roadway of the working face is large, but the mining influence on the roadway below is small. Using FLAC2D, the stress and displacement characteristics of the rock surrounding the obliquely straddle roadway were compared and analyzed when the bolt support, combined bolt and shed support, and bolt–shotcreting–grouting support were adopted, the proposed support scheme of bolting and shotcreting was successfully applied. The deformation of the rock surrounding the roadway was satisfactorily controlled, and the results were useful as a reference for similar roadway maintenance projects.

Under high dynamic load, roadway deformation and failure may occur, posing great challenges. As for now, few studies have been carried out on the impacts of various factors on the deformation of roadway surrounding rocks under high dynamic load, not to mention those on intelligent prediction of the deformation and failure laws. This paper fills these research gaps by studying the deformation and failure characteristics of roadway surrounding rocks and the intelligent prediction method under high dynamic load. The finite difference software Flac3D was used to analyze the influences of roadway buried depth, lithology, and side pressure coefficient on the stability of surrounding rocks and a model was constructed for deformation prediction under high dynamic load. Finally, the influence of various factors on the deformation and their weight was obtained and the deformation can be predicted in line with the BP neural network prediction theory. The results show that the prediction effect is good, with high accuracy.

Cyclic impacts induce progressive fatigue damage at the rock–anchoring interface, thereby compromising the stability of deep roadway support systems. In this study, the split Hopkinson pressure bar and low-field nuclear magnetic resonance techniques were employed to investigate the macro- and micro-scale damage evolution mechanisms of the anchoring interface under varying conditions, including rock type, anchorage angle, and impact air pressure. The results demonstrate that with increasing impact air pressure, both the dynamic compressive strength and average strain rate at the anchoring interface increase. Under cyclic impacts at a constant air pressure, the maximum strain and strain rate increase with each successive impact, while the dynamic compressive strength progressively declines. As the number of impacts accumulates, the total volume of internal pores and pore throats expands, accompanied by a substantial rise in the proportion of large-diameter pores. Changes in elastic potential energy dominate the failure process, which follows a characteristic progression: fissure compression, initiation, propagation, penetration, and final rupture. The observed failure modes include crushing, irregular longitudinal splitting, shear-slip cracking along the interface, and debonding failure. These modes are closely related to the substrate rock strength, interface angle, and impact air pressure. A mismatch in compressive strength and deformation incompatibility between materials were identified as key contributors to failure. Therefore, when selecting anchoring materials, both strength and ductility should be considered to enhance their cooperative load-bearing performance.

To address the challenges of controlling coal roadway roofs with large spans, this study employed theoretical analysis, mechanical modeling, numerical simulation, and field testing to investigate the deformation and failure modes of large-span roadway roofs. An elastic foundation beam model for roof deformation under area support was established. The critical time-effective roof control principle and technology based on area support were proposed. Numerical simulation research and field trials of critical time-effective roof control using area support were conducted in the tailgate (open-off cut) of Panel II513 at the Huaibei Shuanglong Coal Mine. The results indicate that roof stability decreases with decreasing rock beam thickness and increasing span. The deformation and failure modes of large-span roadway roofs include anchor failure within the anchored zone and delamination outside the anchored zone. Case studies based on the mechanical model, numerical simulations, and field tests all demonstrate that the critical time-effective roof control technology utilizing hydraulic support for area support can significantly reduce roof deflection deformation.