Dewatering stress adjustment and effect on mining pressure in deep sandstone roof

To explore the coupling relationship between stress field adjustment and mining pressure in the sandstone roof at great depth under dewatering conditions, a mechanical linkage mathematical model based on elastic theory was constructed to estimate the stress adjustment in the dewatering area and its interaction with mining pressure. Additionally, the Sobol global sensitivity analysis method was introduced to evaluate the importance and interaction of various factors affecting the stress adjustment in the roof area. The study found that the main factors influencing the vertical stress at point M, in order of significance, are the horizontal distance from point M to the dewatering outlet, the pressure head of the aquifer at the dewatering outlet, the permeability coefficient of the dewatering stratum, and the influence coefficient of dewatering; among these, a significant interaction exists between the horizontal distance from point M to the dewatering outlet and the pressure head of the aquifer at the dewatering outlet, while interactions among other parameters are less significant or negligible.