Blast rectangle

You can use this command to create a grid that represents a drillhole blast pattern.

Prerequisites: Graphics is set to plan view. If you want to use the rock name to modify the burden and spacing, a string must be displayed with the rock name stored in the D field of each point.

To run this function: Choose Design > Blast Design > Blast Design > Create blast pattern, or...

In the Function Chooser, type BLAST RECTANGLE, and press ENTER.

You are prompted to drag in Graphics to select the area where the blast holes will appear, and to press F2 to create the holes. You can also drag with the left mouse button to move the area, or CTRL+drag with the left mouse button to rotate the area.

Fields on the Blast pattern design form

Pattern settings tab

Field	Description
Blasting grid
X	The X position of the lower left corner of the grid design box.
Y	The Y position of the lower left corner of the grid design box.
Grid height	The length (burden) of the grid design box.
Grid width	The width (spacing) of the grid design box.
Grid angle	The bearing of the Y direction (burden direction) of the grid design box. That is, the amount by which the grid pattern is rotated from North in plan view.
Blast settings
Pattern identifier	The name of the hole pattern.
Drill rig	The name of the drill rig.
Blasting method	A description of the blasting method for the defined hole pattern. This text is stored in the drill and blast database if you upload the blast holes to the database.
Ground water level	The level of ground water. This text is stored in the drill and blast database if you upload the blast holes to the database.
Burden and spacing
Modify burden and spacing by polygon	Selected: The burden, spacing, and subdrill of each drillhole are determined by the rock type where the hole is located (and the Drill and Blast Settings where rock type details are stored). To specify the rock type, you must create and display a polygon for each rock type, and store the rock type in a D field of the polygon. When you select this option, the Burden/spacing by polygon field options are enabled. Cleared: The burden and spacing of each drillhole are set in the Burden and Spacing fields of this form. Subdrill is set on the Hole Settings tab of this form. The Manual burden/spacing field options are enabled.
Manual burden/spacing
Rock name	The rock mass classification that you want to give to the blast holes. This will be the value of the RMC property for the blast holes you create. Note: In Drill and Blast Settings (Rock Classifications tab), you can see the names and specifications of each rock type.
Spacing method	Burden and spacing: The blast pattern is defined by burden and spacing. Number of holes: The blast pattern is defined by number of rows and number of columns of holes arranged in the selected area.
Burden	The distance between rows of blast holes. This box is visible only when Spacing method is Burden and spacing.
Spacing	The distance between blast holes in the same row. This box is visible only when Spacing method is Burden and spacing.
No. rows	The number of rows of blast holes. The first row is created on the lower line of the design box. This box is visible only when Spacing method is Number of holes.
No. columns	The number of columns of blast holes. The first column is created on the left side of the design box. This box is visible only when Spacing method is Number of holes.
Clip to boundary	Selected: You are prompted to clip the blast holes to an existing boundary string. Cleared: Blast holes are generated over the selected area without any clip.
Burden/spacing by polygon
Rock classification attribute	The D field that holds rock type, in the polygons that mark the boundary of each rock zone.
[Rock type table]	This table displays the burden, spacing, and subdrill for each rock type in the drill and blast settings. If you edit burden, spacing, or subdrill for any rock type in this table, and blast holes are created on that rock type, the new burden, spacing, or subdrill is used.
Blast layout	Staggered: The blast grid pattern is staggered. Rectangular: The blast grid pattern is in rows and columns in which the holes line up vertically.
Hole order	Regular: The order of hole numbering is left to right for all rows. Zig-Zag: The order of hole creation is left to right on the first row, right to left on the next row, left to right on the third row, and so on, changing direction from row to row.

Hole settings tab

Field	Description
Collar elevation
Elevation method	Fixed: The collar elevations of all holes in the pattern is set to the value of the Elevation field. The Elevation field is enabled. DTM layer: The collar elevations of all holes are set to the elevation of a surface in the layer you choose. The surface must be numbered object 1, trisolation 1. This must be a surface and not a 3D solid model. The Layer name, Object ID, and Trisolation ID fields are enabled so that you can specify the surface. DTM file: The name of the surface file. The Location, ID, Object ID, and Trisolation ID field options are enabled so that you can specify the surface.
Elevation	The elevation value of all drillholes.
Make Visible?	Selected: The DTM is displayed in Graphics when the blast holes are created. Cleared: The DTM is not displayed in Graphics when the blast holes are created. This option is visible only when Elevation method is set to DTM file.
Toe elevation
Toe position method	Toe position method is the method Surpac uses to determine the length of each blast hole. Set Length: A fixed hole length is used. The Hole length field option is displayed. Set Elevation: A fixed elevation is used for the toe of all holes. The Elevation field is displayed. DTM layer: The toe position of each hole is determined by its intersection with a surface in a layer. The Layer name, Object ID, and Trisolation ID fields are enabled. DTM file: The toe position of each hole is determined from a surface in the DTM file you choose. The Location, ID, Object ID, Trisolation ID, and Make Visible? options are enabled.
Hole length	The length of all blast holes.
Subdrill distance	The extra drilling length to add to each hole (when Modify burden and spacing by polygon is cleared).
Hole settings
Hole bearing	The bearing (also known as azimuth) of all holes in the pattern. For vertical holes, you can set hole bearing to any value. Zero is typically used for the bearing of vertical holes. The bearing is measured as the azimuth in plan view from the collar to the toe, or end of the hole.
Hole dip	The dip of all holes in the pattern. For vertical holes drilled down, hole dip should be set to -90. For horizontal holes, the dip should be set to zero. The dip is measured as the angle from the horizontal plane to the toe, or end of the hole.
Hole diameter	The hole diameter in units of measure. If the metric system is used, the value is in metres. For example, you would enter a 76mm hole as 0.076 (metres). If the imperial system is used, the value is in feet. For example, a 6 inch hole would be entered as 0.5 (feet). The diameter is written to the D4 field of the first point of the segment which represents the hole.
Labelling options
Hole ID prefix	The numeric hole name. For example, to number the holes 940-1, 940-2, 940-3, and so on, you would enter `940-` as the hole ID prefix. You can leave the hole ID prefix blank. If it is blank, the holes are numbered 1, 2, 3, and so on.
Include rock class?	Select Modify burden and spacing by polygon to enable this option. Selected: The hole ID includes the rock classification. Cleared: The hole ID does not include the rock classification.
Hole ID suffix	The numeric hole name. For example, to number the holes 1rc, 2rc, 3rc and so on., you would enter `rc` as the hole ID prefix. You can leave the hole ID suffix blank. If it is blank, the holes are numbered 1, 2, 3, and so on.
Starting value	The starting number for the incremental part of the hole ID.
Sequence rows	Selected: The hole number of each hole is increased. by (<row number>-1) * Row increment. For example, if the hole number of the first hole in row 4 would have been 1, but Sequence rows is selected, and Row increment is set to 200, the number of that hole is set to 601. Cleared: Holes are numbered sequentially.
Row increment	The row increment for the incremental part of the hole ID.
Pad hole_id	Selected. When the holes are created, the Pad Character is added to the front of the numerical portion of the hole ID. Cleared. The hole ID is not padded.
Pad length	The length of each hole ID, not including prefix or suffix. If the length of a hole ID would be less than this number, the Pad Character is added to the front of the hole ID as many times as needed to increase the length of the hole ID to Pad Length.
Pad character	The character to place in front of the hole identifier.

Output

A blast pattern is generated and displayed in Graphics as a string. The layer called blast hole layer is activated.