Study on characteristics and prevention measures of mine roof water disaster in North Guizhou Coalfield

In recent years, 22 roof water inrush accidents have occurred in North Guizhou Coalfield, which poses a great threat to the safety production of mines in this area. In order to study the characteristics and prevention measures of mine roof water disaster in North Guizhou Coalfield, taking a certain area of North Guizhou Coalfield as the research object, the water filling source, water inrush channel, hydrochemical characteristics and water disaster characteristics of roof water disaster in the research area are analyzed, and the corresponding roof water disaster prevention measures are put forward. It is found that the water quality types of the aquifer of Changxing Formation are SO₄²⁻, HCO₃⁻-Na⁺ , and the water quality types of the aquifer of Yulong Mountain Section are HCO₃⁻, SO₄²⁻-Ca²⁺ and HCO₃⁻, SO₄²⁻-Na⁺, Ca²⁺. The pH value of each aquifer in the area is mainly weakly alkaline, ranging from 7.63 to 8.18. When mining the No.9 coal seam, the water filling source of roof water disaster is mainly the limestone aquifer of Changxing Formation. The characteristics of roof water inrush are strong sudden inrush, large head value, fast attenuation speed, short duration of water inrush, and most of the positions where water inrush occurs are in the lower third of the working face. In response to the problem of roof water disaster in the North Guizhou Coalfield, it is proposed to control the mining speed of the working face and avoid long-term mining stoppage, strengthen the prevention of water disaster during the initial and periodic pressure periods of the roof, as well as advance construction of roof water drainage holes and other water prevention measures. The research results are helpful to the prevention of roof water disaster in North Guizhou Coalfield.