This command is a customized and simplified method for calculating
volumes
in a situation in which the entire volume to be calculated is below the
perimeter elevation, such as in the case of a pond or pit. The
complimentary command, Calculate Stockpile Volume, is for the
opposite situation, in which the entire volume to be calculated is
above the
elevation of the perimeter.
The program
internally computes base and final grid surfaces from drawing
geometry. The base surface is calculated
from a 3D polyline representing the perimeter of the area being
analyzed. If that 3D polyline is drawn on the PERIMETER layer,
the command will automatically detect and use it. If no 3D
polyline is found on that layer, you have an opportunity to manually
select another 3D polyline to use. The 3D polyline perimeter can
be
drawn with the Draw 3D Polyline Perimeter command before using this
routine.
The 3D polyline perimeter is also used as the inclusion perimeter for the volume calculation.
Additional 3D polylines can also be specified to more precisely
define the base surface. These must be on
the BASE_BREAKLINE layer to be used for this purpose. These can
be generated by the Draw 3DPoly Base
Breakline routine.
The final surface is calculated from all of the other selected
drawing entities such as
points,
line, inserts, and polylines,
along with the perimeter polyline, but not including the BASE_BREAKLINE
polylines.
You have the option of setting the resolution of the grids.
The Make 3D Grid File and Two Surface
Volumes commands, used in combination, are an alternative to this
command, and in any situation in which there are cut and fill volumes
between the surfaces, that combination must in fact be used to generate
accurate results.
Ignore Zero Elevations [<Yes>/No]?
Select Pond/Pit entities and perimeter.
Select objects: pick the objects that define the surface and
the 3D polyline perimeter
Select Pond/Pit perimeter polyline:
Make Grid File dialog Set the resolution and then click OK.
Pulldown Menu Location: Grading
Keyboard Command: pitvol
Prerequisite: Data representing the pond/pit surface and a 3D
polyline representing the perimeter of the pond/pit.
File Names: \lsp\stockvol.lsp, \lsp\volcalc.arx