This command applies 2D cross-section dragline steps along a
centerline to create a 3D model. The dragline steps are stored in a
sequence file (.SEQ file) that can be created by the Cut &
Place, Cut Only, Dozer Push, Flatten Spoil Top and Blast Cast
commands.
There are two different methods for Process Dragline Sequence. The Multiple Along Centerline method applies the dragline sequence along a centerline for a range of stations. The centerline defines the dragline alignment and the mining surfaces are defined by grid files and/or section files. This method outputs section files, 3D polylines and a volume report. The Single Section Polyline method applies the dragline sequence to one station in cross section view. The dragline position is defined by picking the centerline position in section view and entering the elevation at this point. The mining surfaces are defined by picking polylines for the ground surface and strata in section view. The output is drawn as polylines in section view for this one station.
Each of the steps has a centerline reference point and the control points for the step are relative to this reference point. For example, the top of the spoil pile for Cut & Place could be 75 feet right of the centerline. Process Dragline Sequence runs the steps along the centerline. A centerline file (.CL file) can be created from a polyline with the Polyline to Centerline command.
The existing ground can be modeled by either a grid file (.GRD file), triangulation file (.TIN file) or section file (.SCT file). Process Dragline Sequence works by repeating the 2D cross-section steps for each section along the centerline. When using a grid file surface, the program will prompt for a station interval and will create ground cross-sections at the specified offset left and right of the centerline at this interval before applying the dragline steps. When using a section file surface, the program will apply the dragline steps at the interval of the section file. There is an option to output the results of dragline steps to a section file. Besides outputting the final section results, sections at the end of each step can be saved to section files. The section files of each step are named automatically by adding the step sequence number to the original final section name.
The dragline steps have an option to use a strata polyline which makes the control points relative to the strata. If strata polylines are used, then the Process Dragline will prompt for a grid file that models the strata. For example, you could use a use a top of coal polyline in the Cut & Place command to define the bottom of the cut area. With the store sequence file (.SEQ) option on, the program will prompt for a name for the polyline and you could enter "coal". This name is stored in the sequence file and when Process Dragline Sequence in run, the program will prompt for you to select the "coal" grid file.
The program creates a report of the volumes for each step in the
sequence. The Coal Density field in the dialog is used for
calculating the coal tons for the report. The Taper Spoil Sides
option adds stations before the first cut and after the last cut to
show the repose angle of the ends of the fill spoil piles. There
are options to draw 3D polylines of the pits. Draw Pit Polylines
creates 3D polylines parallel to the centerline along the dragline
control points such as the top of the spoil pile. Draw Cross
Section Polylines creates 3D polylines perpendicular to the
centerline for each cross section.
Process Dragline Sequence dialog
Station interval <100.0>: press Enter
Processing step> 1
Processing step> 2
Drawing offset 3D polylines: STEP1-SPOIL3
Drawing cross section 3D polylines
Writing section file> D:\SC14\DATA\final.sct
Pulldown Menu Location: Surface in Advance Mining
Keyboard Command: steps
Prerequisite: Centerline file, Sequence file and surface
grid file