36 / 2023-03-29 18:10:38

Optimization of simultaneous mining and control scheme of multiple coal seams ：A case study of mine-crop overlapped zones in central Henan Province

Land reclamation;Remote sensing technique；Mine-crop overlapped zones;Multi-coal seam mining;Numerical simulation

The direct impact of underground coal mining on the ground is the surface subsidence deformation, which in turn affects the crops and vegetation above the surface. Especially in the mine-grain composite area with high underground diving level, the problem of farmland waterlogging caused by coal mining is more worthy of attention. The Concurrent Mining and Reclamation (CMR) highlights the reclamation of the subsidence area in the process of dynamic subsidence. Therefore, it is necessary to carry out dynamic simulation analysis on the high groundwater level mineral grain composite area. This paper chooses Jiulishan Mine which meets the conditions of high groundwater level mineral grain composite area as the research area. Firstly, the spatial distribution, boundary range and underwater topographic information of the surface water area caused by underground coal mining are quantitatively analyzed by using the UAV high resolution remote sensing image and the unmanned ship underwater topographic survey system. Secondly, the fast Lagrangian analysis of three-dimensional continuum (FLAC3D) is used to invert the surface subsidence law and the evolution characteristics of the surface water area caused by different mining schemes. Finally, the filling and excavation volume, reclamation rate and effective land use time simulated by different mining schemes are compared. The results show that：(1) multi-seam mining leads to the gradual increase of mining subsidence area and water accumulation area, resulting in the loss of a large amount of cultivated land. (2) Through the optimization of mining layout, the spatial and temporal distribution of mining subsidence area is effectively changed, which provides a prerequisite for the formulation of ecological restoration planning. (3) Compared with the traditional mining control scheme, after optimizing the mining layout, the duration of reclamation and the amount of reclamation work are greatly reduced, and the effective utilization time of land is further improved. On the basis of optimizing the coal mining scheme, the suitable land reclamation method is selected according to the characteristics of the subsidence area, and the ecological restoration and management plan is formulated. These methods can provide data and technical support for the ecological restoration and management of the mine-grain composite area under the condition of high groundwater level, and improve the ecological, economic and social benefits of the ecological restoration and management of the subsidence area.