Feasibility study of synergistic anchoring and supporting in coal entry heading faces with moderately stable surrounding rock

The support method in coal entry heading faces significantly impacts the stability of surrounding rock and heading efficiency. To enhance heading efficiency while ensuring the stability of surrounding rock, this study takes the 011813 headgate heading face in Jinfeng Mine. Addressing the technical conditions and the demand for rapid heading, an innovative partitioned support approach of "local anchoring + non-repeated temporary support" and "rapid reinforcement anchoring" is proposed. Field investigation, theoretical analysis, and numerical experiments are employed to systematically study the synergistic effect of anchoring and supporting in heading faces. The technical principles of synergistic anchoring and supporting are detailed, the mechanical model of surrounding rock under this system is established, and the strength of temporary support under this system is established. By using a systematic analysis method, parameters for local anchoring, temporary support, and reinforcement anchoring are proposed. Numerical experiments are conducted to comparatively analyze the stress evolution, damage and deformation characteristics of surrounding rock under conditions of no support, timely one-time anchoring, and synergistic anchoring and supporting. The influence of synergistic anchoring and supporting on the stability of surrounding rock is examined, the mechanism of synergistic anchoring and supporting is revealed, and the rapid heading process using this approach is optimized. Based on the findings, the feasibility of synergistic anchoring and supporting is evaluated from the perspectives of technical principles, surrounding rock stability characteristics, support mechanism, and rapid heading processes. The research indicates that the proposed approach holds great potential for field application in Jinfeng Mine. In subsequent heading practices, it is recommended to adjust the unsupported roof distance and unsupported roof distance based on actual conditions, fine-tune the partitioned anchoring parameters, focus on the effective control of surrounding rock through local anchoring, and enhance both the load-bearing capacity and cooperative deformation ability of temporary supports.