Patent ID: 7418373

Claim:
A method of assigning positions for boreholes at a bench blasting site, wherein the rock face has one or more rock face irregularities, the method comprising: inputting one or more bench characteristics of the bench blasting site, one or more blast design constraints, and a proposed drill line having a start point and an end point into a computer; and using the computer to automatically determine a drill position for each borehole and one or more drill pattern characteristics of each borehole based on the blast design constraints, the one or more bench characteristics, and the one or more rock face irregularities, wherein said computer determines a drill position for each borehole by: (1) determining a target rock burden for an initial borehole having a predetermined diameter and depth at the start point; (2) defining along the proposed drill line a progression of successive layers of rock each defining an incremental burden, determining a cumulative burden of successive defined layers; (3) comparing each cumulative burden with the target burden; (4) revising the drill position for the borehole on the drill line in the layer most distant from the start point; (5) defining additional successive layers of rock until the blast constraints of the borehole at a drill position causes the target burden to remove the rock burden associated with the borehole; (6) setting a location for a distant boundary of the rock burden for the borehole; and (7) using the distant boundary as the drill position for an additional borehole and repeating (1), (2), (3), (4), (5) and (6) for each additional borehole until a layer coincides with the end point to calculate the drill position for each borehole; and outputting a report containing the drill position of each borehole.