Physical simulation experiments on mining-induced water inrushes from coal seam floors: Advances in research and prospects

Objective Water inrushes from floors are subjected to the superimposed effects of factors such as specific geological structures, water-rock-stress coupling, and mining disturbance, proving complex, concealed, and abrupt. Methods Physical simulation experiments can effectively reproduce the environments of the floors and confined water, intuitively present the whole process of both mining-induced fracture propagation in the floors and the path evolution of water inrushes, and obtain multi-source data of all disaster stages in a real time manner. Therefore, such experiments enjoy unique advantages in investigating water inrushes from floors. Results and Conclusions This study reviews the research achievements in water inrushes in terms of classical theories, standards and specifications, simulation experiments, and engineering practice, highlighting three advances in research: experiment loading devices and water pressure simulation methods; the R&D and characteristic indices of similar materials, and monitoring technologies and their observation system design. A breakthrough has been made in capturing the whole-process information of water inrushes from floors using a 3D model under the simulated water-rock-stress coupling environment. In the broad context of research on digital intelligence, this study analyzes the limitations of physical simulation experiments on water inrush from floors. Accordingly, it proposes that future development should focus on the R&D of large-scale, comprehensive 3D experiment platforms for water inrush from floors, the establishment of a standardized database for multi-characteristic proportioning of similar materials, the construction of a multi-phase, multi-field, and multi-dimensional coupling monitoring and early warning system, and the integrated application and research of digital intelligence technologies including artificial intelligence. The insights of this study will assist in improving the level of physical simulation experiments from the aspects of devices, materials, and technologies, thereby supporting the high-quality advancement in fundamental research on the intelligent prevention and control of water hazards from floors in coal mines.