Jing Wang

With the continuous expansion of the depth and scale of mining, the mined-out area poses a major threat to the safety of mine production, the surrounding environment, and the lives of residents. Because of the potential safety hazards caused by the large-scale collapse of the mined-out area of metal mines, a treatment plan was formulated in combination with the actual geological conditions of the mined-out area under a metal mine in Henan Province. Through the comparative analysis of the treatment scheme, the blasting caving method is preliminarily selected to control the mined-out area. Considering that the roof of the mined-out area of the mine is strong and the area of the mined-out area is large, an optimized blasting caving method—Underground induced caving and roof cutting technique scheme. Considering the influence of geological conditions and surrounding rock, Flac3D was used for numerical simulation calculation, and the design of the Underground induced caving and roof cutting technique scheme and blasting operation was formulated. By canceling the pressure relief skylight project, unnecessary engineering expenditure is avoided, and the investment structure of the project is optimized. Through the on-site blasting practice, the roof of the mined-out area gradually collapses, and the precise damage induction of the roof of the mined-out area is realized. Finally, a stable waste rock overburden is formed, which effectively prevents the occurrence of sudden roof caving and significantly reduces the risk of mine safety production. It provides technical ideas and practical experience for the treatment of mined-out areas under similar geological conditions.