Tailings dam failure accidents occur frequently, causing substantial damage and loss of human and animal life. The prediction of run-out tailings slurry routing following dam failures is of great significance for disaster prevention and mitigation. Using satellite remote sensing digital surface model (DSM) data, tailings pond parameters and the advanced meshless smoothed particle hydrodynamics (SPH) method, a 3D real-scale numerical modelling method was adopted to study the run-out tailings slurry routing across real downstream terrains that have and have not been affected by dam failures. Three case studies, including a physical modelling experiment, the 2015 Brazil Fundão tailings dam failure accident and an operating high-risk tailings pond in China, were carried out. The physical modelling experiment and the known consequences were successfully modeled and validated using the SPH method. This and the other experiments showed that the run-out tailings slurry would be tremendously destructive in the early stages of dam failure, and emergency response time would be extremely short if the dam collapses at its full designed capacity. The results could provide evidence for disaster prevention and mitigation engineering, emergency management plan optimization, and the development of more responsible site plans and sustainable site designs. However, improvements such as rheological model selection, terrain data quality, computing efficiency and land surface roughness need to be made for future studies. SPH numerical modelling is a powerful and advanced technique that is recommended for hazard assessment and the sustainable design of tailings dam facilities globally.

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To better understand the mechanical behavior of the compression deformation of backfill under high stresses corresponding to large depths, consolidation compression tests were performed for cemented tailings backfill with a cement-sand ratio of 1:10 and a concentration of 70 % under confined conditions. After applying different loading stress functions from 0.5 to 32 MPa, the final axial deformation of the test specimen of backfill was obtained, and the micromorphology of backfill was studied before and after consolidation by scanning electron microscopy. Additionally, fitting analysis was performed for backfill confined compression deformation data and device model constitutive equations by the minimum square law, and the constitutive model was revised according to the analysis results. The research results indicate that as the load increases, the void ratio e obeys the functional relationship e=algt + b with compression time t. Under the high-stress conditions of confinement, the constitutive model of backfill consolidation and creep can be used to describe the creep behavior of the backfill. Under high-stress conditions, after the consolidation of the confined backfill, the space between the tailing particles diminishes, the particles become more compact, and particle slippage occurs.

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To manage heat load problems in deep mining, a research program for measuring and predicting the underground environment parameters was carried out in Jiudian gold mine. The deposit is buried from 150 to-950 m underground. The development drifts reach the-710 m Level and the mine's main production levels are at-510 and-550 m. The mine encountered several hot springs, though blocked, the springs still affect the underground environment. Some environment parameters were measured at three mining levels in summer and winter, including the temperature and moisture of air flow, and the temperature of the rock face and of the internal rock mass. Based on the energy conservation law and the mass conservation law, an environment parameter prediction model was built, and the corresponding computer program was developed using C++ language. Comparison of predicted and measured data proved the reliability of the environment parameter prediction model.