Structural and water stability characteristics of surface soil over shallow-buried coal seams: Spatial variability...

The process of the impact of mineral mining on the surface environment is a chain transmission process from soil structural characteristics to water stability characteristics. Studying its co-inertia is crucial for the assessment of the mining area environment. This study surveyed and tested the structural characteristic parameters and water stability characteristic parameters of the soil in different regions and at different depths of the 61201 working face of the Dafanpu Coal Mine, established geometric models of soil fissure development and spatial distribution models of water stability characteristics, and analyzed the co-inertia of structural characteristic parameters including porosity, equivalent pore diameter, pore roundness ratio, Euler number, pore connectivity rate, and water stability characteristic parameters including moisture content, bulk density, particle size distribution, MWD, GWD, W_R > 0.25, PAD. The research results show that the most significant areas of deterioration in moisture content, bulk density, texture, and aggregate are the fissure positions in the tensile subsidence zone. The peak decrease in moisture content before and after coal mining is 51.8 %, the peak decrease in bulk density is 12.8 %, and the peak destruction rate of aggregates is 84.3 %. The control group soil is mainly loam, the non-fissure position soil in the mining area is mainly sandy loam, and the fissure position soil in the mining area is mainly loamy sand. The damage transmission from structural characteristics to water stability characteristics in non-fissure positions of the mining area soil is more significant than that in fissure positions, with co-inertia correlation coefficients of 0.972 and 0.933, respectively. The research findings reveal the complex interaction mechanism between the soil structural characteristics and water stability characteristics in the mining area, providing a theoretical basis for the formulation of soil protection strategies in the mining area.