2.0

Chapter 4 Working with Cross Sections
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area of the cut or fill at the next station divided by two, multiplied by the
distance between the stations. The commands calculate all data from the
actual values, but the reported values are rounded to the volume precision of
your choice.
n
Prismoidal Calculation: The prismoidal method of calculating volumes is
more accurate than the average end area method. However, this technique
involves a more complicated calculation and may take a longer time to
process.
The prismoidal method calculation is:
Total sum of cut (or fill) area at first station (A1), cut (or fill) area at second
station (A2) plus the square root value of A1*A2. Divide the total sum by 3
and multiply by the distance between the two sections.
The following prompt is displayed:
Use of curve correction (Yes/No) <Yes>:
4 Specify whether to use curve correction:
n
Type Y to use curve correction.
n
Type N to skip this option.
In normal volume calculations, the length between the end areas on horizontal
curves is taken from the length along the centerline curve. With curve
correction in use, the length is taken from the path of the average centroid of
the areas for a more accurate result. The following prompt is displayed:
Use of volume adjustment factors (Yes/No) <Yes>:
5 Specify whether you want to use volume adjustment factors:
n
Type Y to use volume adjustment factors. You are then prompted for the cut
and fill adjustment factors.
n
Type N to skip this option
NOTE
The values you enter against these prompts are not used in calculating the
subsurface cut volumes. The adjustment factors entered in the Design
Control
ä
Volume Adjustment Factors command are used exclusively. If no
data is entered for any or all of the subsurfaces, then an adjustment factor of
1 is applied.
6 Specify an output file name. Include the path and extension when entering the
file name. The default filename and path are set by the Output Settings
command.
7 Specify the range of stations. The defaults for the beginning and ending stations
are based on the beginning and ending stations of the current alignment.
Accept the default or enter a different range of stations.
The command passes through sections determining surface conditions. The
command reports the surfaces it is calculating as it is generating the report. The
command reports the area, volumes, and mass ordinate of cut for each existing
subsurface. This information is written to an ASCII file that can be viewed or
edited with any text editor.