Overlay Vertical Adjustment
Determines the ideal PGL point
based on the input criteria and the distance from the top of the template to
the existing ground.
You can access this tool from the following:
At each processed station, this command determines the ideal PGL point based on the input criteria and the distance from the top of the template to the existing ground. Each existing ground vertex in the cross section will be tested by measuring the vertical distance between that ground point and the top of the template.
Geometry and corridor must be in the same DGN file for this command to operate.
This command is not available when the geometry is in a reference file because the command creates a vertical alignment and the corridor must reprocess to determine criteria for the vertical alignment.
Vertical Overlay Adjustment dialog
| Setting | Description |
|---|---|
| Backbone Thickness | Specifies the thickness (vertical distance) from the profile grade line (PGL) elevation to the bottom of the backbone components. This value is added to the centerline elevation calculated by finding the Minimum Milling/Overlay control point. |
Each of the 4 images have a Backbone Thickness defined.
- Elevation of Adjusted Vertical
- Backbone Thickness
- Minimun Overlay
- Minimum Overlay = 0.0'
- Minimum Milling Point
- Maximum Milling
| Setting | Description |
|---|---|
| Minimum Mode = Minimum Overlay | When specified, the surface is evaluated for the
point that is, vertically, nearest to the bottom of the backbone. The elevation
of this control point is then used to calculate the elevation at the
centerline, following along the bottom of the backbone.
In the image, a red circle represents the point on the surface nearest the backbone. The yellow dashed line represents the bottom of the template placed on that controlling point. The Elevation of the new Adjusted Vertical is created by adding the Minimum Overlay value plus the Backbone thickness, at the location of the centerline. The image shows a Minimum Overlay value of 0.0', with a backbone thickness defined. |
| Minimum Mode = Minimum Milling | When specified, the surface is evaluated for the point that is, vertically, farthest from the backbone. The vertical adjustment is then made to place the backbone directly on that control point. |
| Minimum Milling with Use Maximum Milling toggle ON | The image shows a template placed using Minimum Milling with a Maximum Milling value specified. Without the Maximum Milling value, the template would be placed on the red control point, however, placing the template at that point would violate the Maximum Value at the location shown (and to the area to the right). Therefore the template is placed instead at the point of Maximum Milling depth. |
| Maximum Vertical Difference | If this value is greater than 0.0, the program will compare the elevation of the Adjusted Vertical at the current station against the elevation calculated at the previous station, and will ensure the difference in the two elevations does not exceed this value |
