Design and application of hydraulic fracturing parameters for directional cutting of overlying strata in deep mining roadway

In recent years, with the rapid development of social economy, the shallow coal resources are basically exhausted, and the focus of resource development has shifted to the deep. However, the high ground stress faced by deep mining face is superimposed on the dynamic load of overlying strata, which makes the surrounding rock of roadway more prone to instability and failure. Aiming at the problem that the 130607 working face in a mine is deeply buried and the roof is thick with many hard rocks, which leads to the large deformation of surrounding rock in the roadway ahead of the working face and is prone to strong ground pressure disasters, this paper puts forward the hydraulic fracturing technology of directional slit in overlying strata to solve the dynamic load impact of the roof. Based on the 1602# geological drilling and other mining technical conditions in the working face, a reasonable scheme of directional hydraulic fracturing of overlying strata in the working face was put forward by theoretical analysis and numerical simulation, and it was applied in the field. The monitoring results show that after the implementation of the scheme, the maximum single-day peak energy of microseisms is reduced by 93.07%, which significantly reduces the dynamic load of key strata in overlying strata of the working face and ensures the safe mining of the working face.