针对煤层群开采过程中巷道支护困难问题，以贵州土城矿212回风石门为工程背景。综合采用现场调研、数值模拟、相似模拟及现场试验等手段，揭示了212回风石门应力演化规律，并提出了“卸−转−固”协同控制技术。研究结果表明：212回风石门遭受破坏的主要原因是煤层群采动过程中存在的地质力学问题导致了围岩失稳。巷道底板及两帮在采动过程中产生不同程度的应力集中。当遭受垂直应力挤压时，巷道底部承受的挤压力较大，而顶部围岩承受的拉伸力较大，由于力学不平衡导致围岩的破坏。基于此提出了“卸−转−固”协同控制技术。通过爆破卸压的方式，利用爆破产生的冲击波引起围岩的震动和应力波动，使表层围岩中原本集中的应力分散到更深的围岩区域，降低表层围岩的应力集中程度。同时，利用爆轰和封孔工艺进一步加固卸压孔周围的围岩，形成两个承载结构。即由巷道支护体形成的内承载体和由深部围岩形成的外承载体。两者相互作用有效承受巷道浅部及深部围岩的应力，并转移到支护结构，起到保护和稳定围岩的作用。利用该技术在212回风石门现场试验，结果显示：使用该技术区域应力长期趋于稳定甚至缓慢降低，巷道顶底板及两帮移近速率分别降低了74.49%及47.67%，底鼓量降低了77.2%。而未使用该技术区域应力出现不同程度的上升，表面位移收敛严重。由此可得，围岩控制效果显著。该技术已成功推广到贵州其他不同地质环境的煤矿，均取得了显著效果。

Aiming at addressing the challenges encountered in roadway support during coal seam group mining, this project focuses on the 212 main return-air cross-cut in Tucheng Mine, Guizhou Province. Through field investigation, numerical simulation, analog simulation, and field tests, the study reveals the stress evolution pattern of the 212 main return-air cross-cut and proposes the collaborative control technology of "unloading-rotating-fixing". The findings indicate that the main cause of failure in the 212 main return-air cross-cut is the instability of the surrounding rock resulting from geomechanical issues during coal seam group mining. The floor and two sides of roadway produce different degree of stress concentration during mining. When the tunnel experiences vertical stress compression, the compressive force at the tunnel’s bottom is greater and the tensile force in the surrounding rock at the top is larger, leading to failure of the surrounding rock due to mechanical imbalance. Consequently, the “unloading-rotating-fixing” cooperative control technology is proposed. The shock waves generated by blasting induce vibration and stress fluctuations in the surrounding rock, dispersing the initially concentrated stress in the surface rock to deeper areas and reducing the stress concentration levels on the surface. Additionally, the surrounding rock around pressure relief holes is further reinforced using blasting and sealing techniques to form two load-bearing structures: the inner carrier composed of the roadway support system and the outer carrier formed by the deep surrounding rock. The interaction between these two components enables them to effectively withstand the stress from both shallow and deep surrounding rock of the roadway, transferring it to the supporting structure and playing a crucial role in protecting and stabilizing the surrounding rock. This technology was utilized during the field test at the 212 main return-air cross-cut with great success. The results demonstrate that the stress levels in the area tend to remain stable or even slightly decrease over time. The convergence speed of the roof, floor, and sides of the roadway is reduced by 74.49% and 47.67%, respectively, while the floor heave volume is decreased by 77.2%. However, in areas where this technique is not applied, the stress levels increase to varying degrees, leading to significant surface displacement convergence. It can be concluded that the control effect on surrounding rock is remarkable. This technology has been successfully implemented in other coal mines located in diverse geological environments in Guizhou Province, yielding remarkable outcomes.