The article is focused on the methods to reduce seismic impact of blasting. The data on consumed explosives and non-electric initiating systems of domestic and foreign manufacture are presented. Delay tolerances are evaluated, and causes of simultaneous blasting in different delay groups are discussed. Blasting design for a specific block and probable explosions of charges in different groups are analyzed. Measured seismic effects on surrounding rocks after explosion with the non-electric initiating system are reported. The proposed calculation procedure for delay intervals allows minimizing seismic impact due to blasting on rock mass and enables the increased safety of mining. The procedure is based on the analyses of seismograms recorded at a distance of 150–200 m from a blast. It is required to divide a seismogram into ranges with respect to the amplitude. First, the number of peaks is determined in each range, and, then, the range with the most peaks (the highest repetition frequency) is picked up; this range conforms with the number of charges having the highest repetition frequency as well. Based on these values, a seismicity coefficient is calculated. Later on, the maximum velocity amplitudes are selected, and weight of a charge to generate such velocities is determined. In case that the weight of the charge exceeds the calculated value, the intervals of blasting in the next blocks are increased until the weights of the charges generating the maximum velocity amplitudes equals the calculated values.

Keywords

Seismic impact, non-electric initiating systems, explosion, delay, operational safety.