Research On Slurry Routing SPH Simulation And Hazards Prevention Of Tailings Dam Failure

Tailings dam failure accidents with limited emergency response time and substantial potential threats often lead to heavy casualties and severe financial losses.Despite the significant efforts of China on tailings reusing and recycling,the 2016 documented tailings ponds in China were still as many as 8869.And among them 1425 tailings ponds were designated 'Overhead Tailings Ponds',which indicate the high-risk tailings ponds located upstream and within only 1 km of residential areas,industrial plants,schools,hospitals and other important facilities.Focusing on the problems in hazards prevention,following the clue line of tailings dam failure run-out slurry routings simulation,interdisciplinary methods such as Smoothed Particle Hydrodynamics(SPH),Unmanned Aerial Vehicle photogrammetry and Life Cycle Assessment(LCA)were adopted in this study.The SPH simulation method of tailings dam failure run-out slurry routings on downstream real terrains was studied,in order to avoid the numerical error caused by terrain,similarity ratio and mesh distortion.In addition,the improvement measures for the tailings dam failure hazards prevention were proposed.And the environmental impacts of the traditional tailings slurry piping discharging method and dry stacking method were revealed using LCA method.And the improvement directions of discharging methods were suggested.The results are summarized as follows:(1)It is indicated that SPH method is suitable for solving these simulation problems,through the validations by laboratory physical simulation and dam failure accidents.Based on the open-source SPH solver codes and combined with the satellite remote sensing Digital Surface Model(DSM)data,the calculation and validation of large-scale simulation on tailings dam failure routings were carried out on High Performance Cluster(HPC).(2)The simulation method of tailings dam failure run-out slurry routings by integration of DSM and SPH were proposed and applied.The slurry routings process on downstream real terrain was predicted in advance with the designed capacity.The influence of dam height,dam failure width and slurry viscosity on the consequences was revealed.And the protection effects of various layout types of armour blocks were analyzed.(3)Unmanned Aerial Vehicle photogrammetry of tailings pond and its integration with SPH simulation were realized.High resolution orthophoto images and DSM data were reconstructed by Unmanned Aerial Vehicle photogrammetry to realize the omnidirectional surveillance and inspection of tailings pond and surrounding areas.The resolution was up to 2.63 cm/pixel.In addition,tailings dam failure slurry routings simulation with higher resolution was realized by integrating the reconstructed results and SPH method.(4)Several specific improvement measures for dam failure hazards prevention method were put forward and the environmental impacts of various tailings discharging methods were revealed.The life-cycle environmental impacts of various tailings discharging methods were calculated using LC A method,based on the case study of an iron mine in Northern China.Furthermore,the improving directions were pointed out accordingly.SPH numerical simulation is a powerful and advanced technique that is recommended for tailings dam failure hazards prevention and emergency management domestically and globally.