Design a level terrain (DTM Design macro)

You have created a terrain model from a survey, representing the existing condition. Now you want to calculate the earthworks needed to, for example, level out height differences with minimal soil movement. Alternatively, the terrain may need to be levelled under a specific slope.

The 'DTM Design' macro calculates a new digital terrain model (DTM) for you based on the entered parameters, resulting in a designed condition calculated for you.

STEPS

1. Ensure the terrain model you want to level is active, for example, a DTM of the existing terrain.
2. Draw a line or path. This line is needed to determine the direction of the longitudinal profile. The start and end points must fall outside the DTM.
3. Select this line or path.
4. Ensure the DTM Design macro is active. Then, from the menu, choose DTM Design > Create DTM.
5. Confirm whether you want to perform a levelling calculation for the active DTM. Click Yes.
6. The window for entering parameters to create the DTM opens.
7. Fill in the parameters and click OK.

Pythagoras calculates a new terrain model that approximates your parameters as closely as possible.

Settings for the calculated terrain model

Name

The name you want to give to the new DTM.

Grid

The elevation points of the new terrain model are placed according to a grid. You can determine the distance between the points on this grid.

Connect to Existing Point

To make the designed terrain model connect to a specific existing situation, such as connecting to an access road or the existing ground level, you can set this here by clicking on 'Select Point' and indicating the point in the drawing.

Cross section along path

Set the desired shape of the Longitudinal Profile

Options:

• Leave the profile unchanged in the longitudinal direction.
• Make the profile linear, either under a specific slope or by entering a specific height difference.
• Design the profile in the shape of a circular arc by entering a radius or a height difference.
• Define the profile using 3 slopes, where you need to enter 5 values.

Example circular: 

Example 3-slopes-profile:

Cross section perpendicular to path

Set the desired shape of the Cross-Sectional Profiles

• Roof Profile
• Either by left and right slope percentage
• Or by height difference
• Define Circular Profile by
• Either radius (m)
• Or height difference (m)