DField quick reference
This is a quick reference of all the description fields used in the road design process grouped by function.
This is a very useful reference when you are setting up your data to work with the road design process.
Design horizontal alignment
DFields created by the design horizontal alignment function.
These DFields appear only on the first point of the design.
| DField
|
Purpose
|
| D1
|
Name for the road. This is only set on the first point of the design segment. |
| D2
|
Chainage interval used to create the road centreline |
| D3
|
Initial chainage used to create the road centreline |
These DFields appear on every inflection point in the design segment
| DField
|
Purpose
|
| D4
|
The radius of the circular curve created |
| D5
|
The transition length at the inflection
point |
| D6
|
The superelevation at the inflection
point |
DFields in the centreline created by Design horizontal alignment
| DField
|
Purpose
|
| D1
|
Name of the road |
| D2
|
Chainage of the point |
| D3
|
Design information of the point. It can be one of these
- Tangent Point:
Indicates the point where a straight piece of road changes into either
a transition curve or a circular curve.
- Circular Curve:
Indicates the start and end of a circular curve created from an inflection
point. This only appears if transition curves have been used. If transition
curves haven't been used, then "Tangent Point" will mark the
change from straight line to circular curve.
- Blank.
This indicates a point either in the middle of a straight piece
of road, or in the middle of a curve
|
| D4
|
Superelevation field. These values are
used by the Create road outline function to give the road superelevation.
These values are filled in only on points marked "Tangent Point"
or "Circular Curve". The Create road outline function linearly interpolates between these to produce the superelevation. |
Create longitudinal profile
DFields used by create longitudinal profile
| DField
|
Purpose
|
| D2 (optional)
|
Chainage of the point |
Design vertical alignment
DFields created by design vertical alignment
| DField
|
Purpose
|
| D5
|
The curve length used to create the vertical
curve. |
|
|
|
Apply longitudinal profile
DFields created by apply longitudinal profile
| DField
|
Purpose
|
| D2
|
Chainage of the point |
Create road outline
DFields used by the create road outline function.
| DField
|
Purpose
|
| D2
(optional)
|
Chainage of the point |
| D4 (optional)
|
Superelevation
field. These values are used by the Create road outline function
to give the road superelevation. These values are filled in only on points
marked "Tangent Point" or "Circular Curve". The Create
road outline function linearly interpolates between these to produce
the superelevation. |
| D6
(optional)
|
Left
road width. If desired, you can specify the left hand road width
at various points along the road. Any point that does not have a road
width specified will just have it linearly interpolated using the chainage
values along the road centreline. |
| D6
(optional)
|
Right road
width. If desired, you can specify the left hand road width at
various points along the road. Any point that does not have a road width
specified will just have it linearly interpolated using the chainage values
along the road centreline. |
