Study on Prevention and Control Measures of Water–Sand Inrushes Based on Adaptive Adjustment of Mined Thickness

There have been frequent occurrences of water–sand inrushes in underground mines due to irregular mining activities under thick loose gravel layers. The morphological development characteristics the caving zone and changes geological conditionsin working face a sedimentlayerof Pingan Coal Mine studied. empirical formula numerical simulations are carried out explore effect different thicknesses bedrock on height zoneand thickness. method solving water-sand inrush fully mechanized by adjusting thickness was proposed. results indicate that there is linear relationshipbetween mined ratio decreases with an increase correlation can be described power function. maximum allowable determined based bedrockand changed tendency ratio. This provides mean control stability sand layer roof coal. has applied mine prevent successfully.