Blasting Method

Abstract

Methods for evaluating drill pattern parameters such as burden, spacing, borehole diameter, etc., at a blast site are disclosed. One method involves accumulating the burden contributed by successive layers of rock and matching the accumulated rock burden to a target value for a borehole having a length related to the average height of the layers. Another method relates to varying drill pattern parameters and characteristics to match blast design constraints, including the substitution of one explosive material for another by the proper balance of materials and/or output energies to the associated rock burden. Analysis of deviations from target rock burdens and corrective measures are disclosed, as well as cost optimization methods. The various methods can be practiced using an appropriately programmed general purpose computer.

1 - 25 . (canceled) 
   
   
       26 . A method for determining a priority-directed loading configuration for a borehole subject to blast design criteria, the method comprising:
 (a) selecting a segment of the explosive column portion of the borehole to be filled with explosive material;   (b) determining the rock burden associated with the identified segment;   (c) evaluating candidate explosive materials for use in the identified segment in order of priority until one is found that meets the blast design criteria (referred to herein as a compliant material), and assigning the first compliant material to the selected segment, assigning stemming to the segment when all the candidate explosive materials fail to meet the minimum energy factor criterion and indicating whether all the candidate explosive materials exceed the maximum energy factor criterion; and   (d) repeating steps (a), (b) and (c) for each segment of the explosive column.   
   
   
       27 . The method of  claim 26  wherein explosive materials are evaluated in order of cost to generate a cost-directed loading configuration. 
   
   
       28 . The method of  claim 27  wherein explosive materials are evaluated in order of specific energy. 
   
   
       29 . The method of  claim 26  further comprising assigning stemming to the segment when each evaluated explosive material provides less than a minimum energy factor criterion for the rock burden. 
   
   
       30 . The method of  claim 26  or  claim 29  further comprising assigning an “unknown” to a segment for which all candidate explosive materials exceed the maximum energy criterion and continuing the method until each segment of the borehole is evaluated. 
   
   
       31 - 36 . (canceled) 
   
   
       37 . A computer-readable medium having computer-executable code therein, the medium comprising:
 (a) code for selecting a segment of the explosive column portion of a borehole to be filled with explosive material;   (b) code for determining the rock burden associated with the selected segment and for accessing data pertaining to blast design criteria comprising minimum and maximum energy factors and for accessing data pertaining to candidate explosive materials;   (c) code for evaluating candidate explosive materials for use in the selected segment in order of priority until one is found that meets the blast design criteria (referred to herein as a compliant material), and for assigning the first compliant material to the selected segment, for assigning stemming to the segment when all candidate explosive materials fail to meet the minimum energy factor criterion, and for indicating whether all candidate explosive materials exceed the maximum energy factor criterion; and   (d) code that causes code (a), (b) and (c) to repeat for each segment of the explosive column.   
   
   
       38 . The medium of  claim 37  comprising code for evaluating explosive materials in order of cost to generate a cost-directed loading configuration. 
   
   
       39 . The medium of  claim 38  comprising code for evaluating explosive materials in order of specific energy. 
   
   
       40 - 45 . (canceled) 
   
   
       46 . An apparatus for assigning positions for boreholes of predetermined diameter for use with a specified explosive material along a primary drill line along a bench of rock having a known density and a rock face, the apparatus comprising:
 a computer processor;   at least one storage medium accessible to the processor, for storing data and executable code;   input means for delivering data to at least one storage medium; and   output means for conveying data representing locations of boreholes;   wherein the storage media comprise a storage medium as set forth in  claim 37 .   
   
   
       47 . The medium of  claim 38  comprising code for permitting code (vi) to repeat code (iv) and (v) until an energy factor criterion is not met. 
   
   
       48 - 50 . (canceled)