Theory and technological system of advance sequential pressure-relief mining in deep metal mines

Deep metal mining operations are confronted with extremely complex geological conditions characterized by notably high in-situ stress. The continued reliance on theories and technical systems developed for shallow mining readily induces rockbursts and other mining-induced disasters, severely constraining the safe and efficient extraction of deep mineral resources. This paper systematically reviews the current state and core technical bottlenecks of deep metal mining worldwide, and proposes an advance sequential pressure-relief mining theory centered on proactive ground pressure control. The theory partitions ground pressure regulation into two hierarchical levels, specifically, advance regulation and sequential regulation. Advance regulation focuses on optimizing the mining method, stope structure, and extraction sequence prior to mining, with the aim of establishing a low-stress mining environment. It constitutes strategic ground pressure control. Sequential regulation concentrates on dynamically intervening in the evolution of mining-induced stress during the extraction process through techniques such as pressure-relief blasting and self-bearing active support, so as to address local ground pressure anomalies. It constitutes tactical ground pressure control. Within this theoretical framework, seven key technologies are proposed, including three-dimensional visualized engineering disaster modeling and deep mining methods, forming a full-chain closed-loop technical system that follows the sequence of "geological cognition, advance design, process early warning, dynamic regulation, and data feedback." This system drives a paradigm shift in ground pressure management from passive response to proactive prevention and control. The relevant technologies have been successfully applied in multiple deep mines. Notably, the portal-arch stope structure reduces preparation work by over 40%, and the J-type energy-absorbing rock bolt achieves an energy absorption of 46.5 kJ under minimal displacement. These advancements provide theoretical references and engineering support for the safe and high-quality extraction of deep metal resources.