2.0

Calculating Cross Section Volumes
435
Calculating the Volume Data and Displaying the
Results in a Table
The Volume Table command calculates the cut and fill volumes of a range of
cross sections and creates a table of the data generated.
To calculate the cut and fill volumes of a range of cross sections and create a
table of the data generated
1 Generate the cross section areas using the Edit Design Control command, if you
haven't done so already.
2 From the Cross Sections menu, choose Total Volume Output ä Volume Table.
The following prompt is displayed:
Volume computation type (Prismoidal/Avgendarea) <Avgendarea>:
3 Specify the volume computation type, Prismoidal or Avgendarea:
n
Average End Area Calculation: For the average end method, the
calculations for volumes takes the area of cut or fill at one station plus the
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.
A prompt is displayed asking if you want to use curve correction.
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.
A prompt is displayed asking if you want to use volume adjustment factors.
5 Do one of the following to 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.