关键词: 永久散射体(PS), 合成孔径雷达干涉测量(InSAR), 工业广场, 沉降监测, 相干系数, 振幅离差指数

Abstract:

To ensure the safety of the mining ground and underground workers, residents around the industrial square, and the operation of the coal transportation system, real-time monitoring of surface deformation is carried out. An optimized method for acquiring PS points is proposed to enhance the applicability of PS-InSAR technology in settlement monitoring. Firstly, a to total of 26 Sentinel-1A satellite images during the subsidence period of the Industrial Square coal pillar II 513 working face in the Huainan suburban coal mine from October 31, 2020, to August 22, 2022, were selected. The PS-InSAR technology was used to determine the optimal method for selecting PS point targets. Then, based on this method, the ground subsidence rate and cumulative subsidence of the mining damage protection zone during the mining process of the working face were obtained. Finally, the accuracy of PS-InSAR monitoring was verified based on the measured data of ground leveling points, and the dynamic subsidence of the study area's ground and structures was analyzed. The results show that the dual-threshold method of coherence coefficient and amplitude dispersion index is more suitable for subsidence monitoring in the study area. The maximum detectable subsidence rate in the study area is -26.5 mm/year, and the maximum cumulative subsidence value is -53.7 mm. Additionally, geological hazards related to karst collapse were detected in the northwest of the study area. By using leveling data for accuracy verification, the root mean square error (RMSE) is only 3.8mm, and the coefficient of determination reaches 0.91.

Key words: persistent scatterer(PS), interferometry synthetic aperture radar(InSAR), industrial square, settlement monitoring, coherence coefficient, amplitude dispersion index