Use volume tools to display and adjust the elevation of a grading design.
You can change the elevation of either an entire grading group or a selection of grading objects. Use this command to optimize cut and fill requirements.
A dynamic surface must exist for the grading group and a Volume Base Surface must be specified in the Grading Group Properties to use most of the Grading Volume Tools.
If you are designing a detention pond and want to size it by volume, it may help to create a temporary surface to use as the Volume Base Surface for comparison. To do this, draw a polyline around the pond rim, assign it the rim elevation, and add it as breakline data to a surface. When you use such a surface as the Volume Base Surface for the grading group, you can more easily see how much volume the pond can contain.
Tutorial Exercise: Adjusting the Cut and Fill Volumes
To adjust cut and fill volumes
- Click Analyze tab
Volumes And Materials panelGrading Volume Tools
.At the Command prompt, enter GradingVolumeTools. - In the Grading Volume Tools, click
. - In the Select Grading Group dialog box, select a grading group or create a new one.
- Optionally, click
to review and change properties for the grading group.
- Select either Entire Group or Selection to identify the grading objects for which you want to raise or lower to make the volume adjustments. For Selection, click
and select objects in the drawing. - In the numeric field in the upper right of the Grading Volume Tools, enter the distance (typically feet or meters) by which the grading objects will be raised or lowered for each elevation adjustment.
- Do one of the following:
- To manually adjust the grading elevation, click
or 
and note the changed values for cut, fill, and net volume. - To automatically adjust the elevation to meet a net volume target, click
. Enter the target volume in the Auto-Balance Volumes dialog box, then click OK. The elevation is adjusted several times, getting as close to the target as possible.
- To manually adjust the grading elevation, click
Automatic volume balancing is an iterative process, adjusting the gradings up or down in progressively smaller steps to achieve the target volume. Typically the resulting volume is not exactly what was entered as the target value. To prevent it from excessively adjusting and recomputing the volumes, it stops when the result is within a tolerance of 0.1% of the starting net volume. If the result is not close enough to your target volume, you can run the command again.