Abstract:
Major disasters associated with strata movement constitute a predominant share of coal mine accidents. Establishing and perfecting mine pressure control theory is fundamental to controlling these related disasters. Based on a review of the development history of mine pressure theory, this paper summarized and refined the connotation of the ‘practical mine pressure control theory’ centered on overlying strata movement. Key breakthroughs in this theory were examined from three aspects, i.e., theory, technology, and equipment. In terms of theory: A dynamic structural mechanics model of the stope which reveals the evolving patterns of overlying strata movement and abutment pressure distribution was constructed, and the dynamic development characteristics of the model under different mining conditions were determined. The ‘two stress fields theory’ was established, and the conditions for the formation of an internal stress field were clarified. In addition, a mechanical model for working face roof control, with the position equation as its core, was built, establishing the relationship between roof control (load on supports) and the position of the rock beam. In terms of equipment: Equipment such as a three-dimensional similar material simulation test platform and a mine pressure mechanical simulation test platform were developed, which enabled the back-analysis simulation of strata movement laws and abutment pressure distribution. Monitoring instruments like large-range (200–300 mm), high-precision (0.01 mm) roof dynamic monitors were developed, forming a complete set of monitoring equipment and a platform for dynamic strata behavior. Besides, a simulation system for overlying strata movement was established. This system visualizes the mechanical models through computer simulation and facilitates mine pressure simulation and decision-making. In terms of technology: The dynamic observation technology for underground strata was proposed, enabling the prediction of main roof weighting. Meanwhile, the technology of gob-side entry driving with narrow coal pillars was developed. By positioning extraction roadways within the stable internal stress field, this technology successfully controls dynamic disasters such as rock bursts and gas outbursts induced by traditional roadways protected by large coal pillars. Finally, the philosophical essence of the ‘practical mine pressure control theory’ was distilled, characterized by strategic foresight, functionality orientation, practical effectiveness, and risk aversion. Five key frontier directions for future breakthroughs were identified: extreme mining conditions, controlled strata movement, regulated mining-induced stress, utilization of mine pressure, and non-intrusive control.