Abstract: Based on the mechanical property of wall rock at depth and the principle of detonation dynamics, the paper analyzes the effect of the blasthole depth on the cutting efficiency in roadway heading and discusses the common cutting modes in medium and long-hole blasting. The parameters of cutting-blasting, perimeter smooth surface blasting and explosive load in large cross-section roadway heading in hard rock at depth are calculated and the other issues needing attention in the construction are also elucidated, which will be of certain guidance significance to the selection of site blasting parameters and construction.

Key words: Hardrock roadway, Medium and long holes, Deep underground mine, Cutting blasting