The Optimization of Segmented Reaming Parameters and the Analysis of the Pressure Relief Effect in Impacted Coal Seams

Abstract

This work focused on the insufficient or excessive pressure relief in large-diameter pressure relief by drilling. The influence of large-diameter pressure relief by drilling on the 6307 working face of the Tangkou coal mine on the roadway deformation was taken as the research background, with numerical simulations, indoor experiments, and on-site applications used. The influence of pressure relief drilling on roadway deformation was studied to propose segmented reaming pressure relief. The influences of parameters (e.g., reaming diameter, reaming depth, and borehole spacings) on the evolution characteristics of segmented reaming cracks and pressure relief were further investigated. The results showed that segmented reaming pressure relief reduced the roadway deformation and the peak elastic energy of coal in the impacted hazard area and improved the energy accumulation of the surrounding rocks of the roadway. The effect of segmented reaming pressure relief was positively correlated with the diameter and length of the reaming section; it was negatively correlated with borehole spacings. The optimized segmented reaming parameters of the 6307 working surface of Tangkou coal mine are as follows: the optimized reaming diameter of 240 mm, the reaming section depth of 15 m, and the borehole spacing of 1.6 m. Field tests proved that the optimized segmented reaming technology can improve the deformation of the surrounding rocks of the roadway and construction.