124 / 2023-06-20 14:44:00

Delineation Method and Application of Backfill Mining influence Range Based on Fusion of Coal Mining Subsidence Principle and InSAR Monitoring

backfill mining; surface subsidence; InSAR; 3D deformation; influence area delineation

Delineation of surface subsidence range (10mm) in coal mining is directly associated to the compensation standard for mining damage to ground structures, and precisely delineating the subsidence area of coal mining can also avoid disputes between workers and peasants and relive conflicts between coal mining enterprises and residents. However, the current determination of the affected area of coal mining mainly relies on geometric method or prediction by probability integral method, and the delineation error is relatively high, which is liable to cause disputes between workers and peasants, and is not conducive to the sustainable development of the region. Meanwhile, the continuous improvement of Synthetic Aperture Radar(SAR) technology enables to delineate the subsidence of coal mining through measurement with high precision, especially for the delineation of the subsidence with small earth surface deformation and large subsidence. The paste filling face of a mine in Shandong of China is studied in the paper, the mining earth surface subsidence information of the filling face of a mine from March 2018 to June 2021 is obtained with the 97-view orbital Sentinel-1A data and Small Baseline Subset(SBAS) technology. Related to the surface leveling measurement results of 46 observation stations, it can be concluded that the average standard deviation of the SBAS monitoring results is 10.3mm, which is difficult to satisfy the requirements of the impact area delineation of the backfill coal mining surface. Thus, combined with the relationship between the subsidence and horizontal movement of the backfill mining subsidence principle, the line-of-sight deformation obtained by  (Interferometry Synthetic Aperture Radar, InSAR) is decomposed into three-dimensional (3D) deformation, and the average standard deviation of the vertical deformation obtained by the 3D deformation decomposition and the leveling measurement outcome is 6.2 mm. Compared to the SBAS monitoring accuracy when ignoring horizontal movement, the monitoring accuracy is increased by 39.8%, meeting the necessities for precise delineation of the surface subsidence for backfill mining. Ultimately, the affected range of backfill mining surface is delineated, and the obtained findings indicate that there is relatively great effect of backfill mining subsidence on Lilin and Mengying villages, and the maximum earth surface subsidence is 150m and 220mm, respectively. The research consequences have important practical significance for determining the damage compensation of the ground buildings (structures) in the mining area and the harmonious development of the mining area.