Abstract:
Aiming at the problem of severe mine pressure behavior caused by the high-strength K2 limestone layer in the working face, a roof presplitting blasting and roof cutting and pressure relief technology is proposed. By forming a weak structural surface in the rock strata to reduce mine pressure impact, optimize parameters such as vertical height, inclination angles, spacings and others of blastholes, deep hole energy gathering blasting technique and water cannon mud hole sealing technology are adopted to achieve precise release of blasting energy and construct a continuous penetration presplitting surface. The on-site application shows that the roof stability is significantly improved, the dynamic load coefficient of mine pressure and the working resistance of the bracket are reduced, the peak value of mine pressure is obviously decreased, and the operational safety is greatly improved.