Existing backfill and
existing contours
This command applies to narrow valleys such as in Appalachia where the goal is to regrade an existing valley fill with benches and specific slopes. Before starting this command you must create grid files (.grd) that represent the existing surface without any fill and the surface with the existing backfill. These grid files can be created with the Make 3D Grid File routine of the Civil Design module.
Regrade Backfill also requires a pre-drawn alignment polyline which defines the shape of the face of the regrade. This polyline must be drawn below the existing backfill and it must be at least long enough to reach across the widest part of the regrade.
To run the routine, specify the two grid files, the alignment polyline, the direction up the valley, the slopes, and the bench dimensions. The program then draws in the regrade as 3D polylines and calculates the cut and fill. To balance the cut and fill, choose the Adjust parameters and redesign option.
Select Existing Surface Grid File
Select Backfill Grid File
Pick existing backfill perimeter polyline: pick a closed
polyline that represents the limits of the backfill disturbed
area
Pick the regrade alignment polyline: pick a
polyline
Pick direction up regrade: pick a point towards the back
end of the valley
Enter the vertical lift between benches
<50.0>: press Enter
Enter the slope ratio (x:1) <2.0>: press
Enter
Enter the bench width <20.0>: press
Enter
Enter the bench percent slope <2.0>:
press Enter
Enter the top percent slope <2.0>: press
Enter This slope is used after the regrade reaches the top
of the existing backfill until the end of the regrade.
Example Regrade Backfill Report:
Regrade Backfill Report
Vertical lift between benches: 50.00
Slope percent: 50.00%, slope ratio: 2.00:1
Bench width: 15.00
Bench slope percent: 2.00 slope ratio: 50.00:1
Top slope percent: 2.00 slope ratio: 50.00:1
Total fill: 13105.1 C.Y., 353840.0 C.F.
Total cut: 13288.2 C.Y., 358782.9 C.F.
Existing backfill and
existing contours
3D view of regrade backfill. Also showing existing contours.
Pulldown Menu Location: Surface
Keyboard Command: backfill
Prerequisite: Grid files of the existing surface and
existing backfill and an alignment polyline.