Use of Weakened Charge in A Compensatory Chink, As A Way of Increase of Operating Ratio of A Borehole at Roadway Driving by Long Stopes in Soft and Viscous Breeds

摘要

The way of increase of operating ratio of a borehole to 0. 98～1.0 for cutting complete of boreholes in the length of 6. 5 m in soft and viscous breeds for the application account of weakened charge of low power which is blown up first in face of the compensatory chink is described.