BlastMCF

Maptek BlastMCF is a web-based application that generates an optimised drill, charge, and timing design. This is accomplished through the Maptek Compute Framework (MCF) to automatically generate a number of blast design solutions within a predefined blast boundary. A solution in BlastMCF is defined as an optimal drill, blast, and timing design.

These solutions are generated by a customised genetic algorithm against a number of targets that the BlastMCF uses to leverage the differences between possible outcomes and quantify the quality of a design. The targets that the BlastMCF can take into consideration are as follows:

  • Cost: The total estimated cost of all components of the blast. This includes drilling, explosive product, primer, and estimates of labour costs involved. These are calculated through the same mechanism as the cost report in BlastLogic (see Cost Report for more information).

  • Powder factor: The ratio of explosive mass per unit mass or volume of rock to be blasted.

  • Vibration: An estimation of the vibration caused by the blast at specified locations of interest measured as peak particle velocity (PPV). See Locations and Vibration Modelling for more details.

  • Fragmentation: An estimation of the distribution of rock sizes that will be produced by the blast, based on the KuzRam model. See Fragmentation Modelling for more details.

  • Fly Rock: The predicted maximum horizontal distance that fly rock can travel as a result of blasting. Fly rock projection is based on either the McKenzie, C.K, 2009 or Richards and Moore, 2006 models (see Methods for more information).

Note:  The BlastMCF calculates 2D fly rock projection only.

Tip:  Specify the area where you don’t want the fly rock to occur by applying an exclusion zone polygon and setting the Fly Rock target as a constraint. BlastMCF will automatically exclude any results with fly rock in that area.

Required data

For BlastMCF to generate blast design solutions, you must supply the following data:

  • Blast boundary polygon by loading the AutoCAD DXF file (.dxf) or Vulcan design database (dgd.isis) file. See Polygon and Export for more information.

  • Upper surface with depth by loading the Vulcan triangulation (.00t) or .dxf file.

  • Lower surface by specifying one of the following:

    • Surface: Load the .00t or .dxf file based on which BlastMCF will define the lower surface.

    • Depth: Enter the required value in the field.

    • RL: Enter the required value in the field.

Note:  BlastMCF will calculate the blast volume based on the boundary polygon, upper surface, and lower surface data that you provide. You can also supply your own blast volume data. To do so, click From file under the Blast volume solid, click Load from file and select the required .00t or .dxf file in the file explorer. In that case, you do not have to provide the upper and lower surface values.

Target outcomes

You can set your targets as either objectives that are optimised or constraints that are adhered to, with the following distinctions taken into account by the algorithm:

  • If you set a target as an Objective, BlastMCF will try to find the optimal value for that target. The more optimal the design against the objective is, the higher BlastMCF will rate the design.

  • If you set a target as a Constraint, the target must fall within the minimum and maximum limits that you specify.

    Note:  You can set a target to be both an objective and a constraint. In this case, BlastMCF will optimise the solution between the set limits and discard any solutions which are outside of that range.

    Note:  If the BlastMCF cannot find a single solution that can satisfy the constraints you set, it will return the result that is closest to meeting the constraints. However, this design solution will be considered invalid.

To achieve optimum results, we recommend that you set competing targets. Competing targets are targets that optimise or constrain different aspects of a blast. For example, fragmentation and powder factor are non-competing targets as they are both related to oversize rock calculations. In contrast, cost and powder factor are competing targets, as they correspond to different properties of a blast.

The following table gives a description of how each target operates when it is set as an objective or a constraint.

Target When set as an objective When set as a constraint Similar
(non-competing)
targets
Cost BlastMCF will try to minimise the cost. BlastMCF will discard any solution that results in cost being outside the specified range.  
Powder factor BlastMCF will try to find the solution closest to the specified powder factor value. BlastMCF will discard any solution with a powder factor outside of the specified minimum and maximum values. Fragmentation
Vibration

BlastMCF will try to minimise the average peak particle velocity of all monitoring points.

Note:  You can create monitoring stations in the Locations tab (Home tab > Setup group > Site > Locations). See Locations for more information.

 BlastMCF will discard any solution where the vibration in any monitoring point exceeds that monitoring point’s limit. Fly Rock
Fragmentation BlastMCF will try to minimise the percentage of rocks that exceed the oversize rock diameter cut-off.

BlastMCF will discard any solution containing rock that is greater than the specified oversize rock diameter cut-off at a percentage greater than the fragmentation violation.

Example:   If you specify an oversize cut-off as 1000mm and set the Proportion Below Cutoff constraint to 90%, a fragmentation violation greater than 10% will be discarded. This would mean that fewer than 90% of the rocks are less than 1000 mm in diameter.

 Powder Factor
Fly Rock BlastMCF will try to find the solution with the fly rock result that is furthest away from the specified exclusion zone boundaries. BlastMCF will discard any solution that includes a fly rock that lands within the specified exclusion zone boundaries. Vibration

Note:  We recommend that you select no more than three competing objectives. Any more will result in very large processing times.

Web access

The BlastMCF URL, just like the server URL, is unique to each user and has the following form:

<serverURI>/web/#/blastmcf, where

<serverURI> corresponds to the URI of the Server that you connect to while using the BlastLogic Desktop application.