Abstract:
The stability evaluation of goaf collapse sites serves as a crucial basis for subsequent engineering construction. The study first adopts the probability integration method to calculate the surface residual movement and deformation values in goaf areas, including residual tilt value, residual curvature and residual horizontal deformation value, and then establishes the site stability evaluation index system by integrating qualitative and quantitative approaches, incorporating factors such as coal mining subsidence rate, cumulative subsidence, surface residual movement and deformation, mining depth-to-thickness ratio, and macroscopic stability of ground collapses and ground fissures. Taking a coal mining subsidence area in Shenyang City as an example for site stability evaluation, the results show that the unstable zone is located in the western part of the study area, covering approximately 1.64 km
2, accounting for 5.13% of the total area. In this zone, the mining depth-to-thickness ratio is greater than or equal to 60, with relatively high current surface subsidence rate(≥ 60 mm/a) and large residual surface movement and deformation values, and the ground collapses and fissures are well-developed and still evolving. The basically stable zone is primarily situated in the eastern part, with an area of 2.34 km
2, representing about 7.32% of the total area. The mining depth-to-thickness ratio is 35-60, with the surface subsidence rate of 30-60 mm/a and moderate residual movement and deformation values. The ground collapse and fissure have largely stabilized.