How can I plan an excavation pit of approximately the same cut and fill in sloping terrain?
The DTM is reduced to the area of the planned building. When you compute the cut and fill and set the data type to 22.014 and the horizon to yes, the horizon represents the base of the pit. You can perform consecutive calculations using different height settings for the horizon. This way, you can quickly produce an approximation of the correct height of the base.
The individual steps:
1. Use lines to draw the outline of the building in the original DTM. The next step is to mesh these lines with the DTM (Modify -> Terrain -> Digital Terrain Model -> Mesh Element with DTM). This adds new points to the DTM. These points are on the end points of the lines and the height is interpolated based on the DTM.
2. Enter an exterior boundary that serves as the outline of the building (Modify -> Terrain -> Digital Terrain Model -> Exterior Boundary). The points required for entering the exterior boundary were created when you meshed the lines with the DTM.
3. Finally, compute the cut and fill using the 22.014 data type (Create -> Terrain -> Digital Terrain Model -> Compute Cut and Fill). In particular, use the following settings: DataTp: 22.014; Horiz: Yes; Analyze: Cut and Fill. Enter the mean height of the DTM as the initial value for the horizon in the Heightbox. Perform some calculations to determine the correct height of the horizon.