Element Data

This window shows data for the individual alignment elements either in the horizontal geometry or in the vertical geometry.

When the alignment is NOT OK please check the color-coding to identify the problem.

Note that the input tables vary between the tabs.

Horizontal Geometry

Vertical Geometry

Ref. Points

Results H and Results V (not covered in the other lists)

From Chainage | To Chainage | K

Horizontal and Vertical Geometry

No.

All elements are numbered chronologically. The number series normally start at 1, but can be changed by the user by simply setting the value manually. This will change all other numbers in the series to correspond.

Element numbering cannot be negative.

Element

Elements in the alignment geometry can be either Straight Line, Arc, Parabolic or Transition Curve.

For vertical geometry only Straight Line and Arc/Parabolic are available.

Note: Changing between Arc and Parabolic curvature is done through Windows system variables. To use Parabolas follow these steps:

Step 1: Close Alignment Design.

Step 2: Open Windows Control Panel.

Step 3: Open System.

Step 4: Open Advanced system settings.

Step 5: In the advanced tab go to Environment Variables...

Step 6: In the System variables create a new variable by clicking on New...

Step 7: Enter the following:

Variable name: VIPS
Variable value: P

To remove the system variable just delete the variable.

Type

The type of fixation determines how to constrain the alignment geometry.

The different fixations available are:

Table 1: The available fixations

Fixed, Partial and Approx. are the most used fixation types used in any typical project.

Combination of fixation

There are many different combinations for fixation that are OK to use and it all comes down to some basic principles:

There must be at least one Fixed element in the list.
Between two Fixed elements there always has to be ONE, and ONLY ONE, Approx. element.
Between two Fixed elements there can be multiple Partial elements if necessary in addition to the Approx. element.

Placement of fixation coordinates

For Fixed elements, there are two fixation points, point A and B. Point A has to come before point B along the alignment.
Make sure that fixation points are not placed too far apart. For instance, for a radius of 10m the fixation points should never be further than 20m away from the direction of the neighboring points/element direction. Then the element is not calculable.

Room for elements to exist

Elements can be squeezed between other elements resulting in no room for them to exist. This will result in an incalculable geometry.

Radius

Gives the start radius of the elements for Arc/Parabolas and Transition Curves.

End Radius

Only available for horizontal geometry.

Only available for Transition Curves after changing the settings found here: Tools > Options… > General > Display > Allow transition curve with end radius...

Gives the option to have a different end radius on the transition curve compared to the adjacent element.
Gives the opportunity to set a user-defined end radius for the transition curve when the geometry ends with this element (in connection to existing roads etc.).

Length

Only available for horizontal geometry.

Gives the length value in meters for the element along the alignment.

Hor. Length

Only available for vertical geometry.

Param.

Only available for horizontal geometry.

Only for Transition Curves and is a value for the correlation between radius and length of road for a smooth transition between Straight Lines and Arcs/Parabolas.

Bearing

Only available for horizontal geometry.

Used for Straight Lines.

Gives the bearing for the Straight Lines looking along the alignment.

Values are given in radians according to the "Unit Circle" (technical term).

Arc Type

Only available for horizontal geometry.

Used for Arcs/Parabolas.

Arc types can be Short or Long and determine if the arc should try to be longer or shorter than 200 gon (180 degrees).

Warning: Longer arc elements than 200 gons can cause problems for the road model calculation.

Slope % or Slope ‰

Only available for vertical geometry.

Only available for Straight Lines and gives the slope value in percent or permit along the alignment for normal situations (Slope direction = Free).

Note: The slope prefix -/(+) (+ is not used) will be used in conjunction with the slope direction.

To change between percent or permil go to Tools > Options > Vertical tab > Slope as…

Slope Dir.

Only available for vertical geometry.

Set the direction for the slope to be fixed.

Free - Start and end fixation points are movable/editable separately.
Forward - The first fixation point is movable/editable only. The last fixation point will not move if you are trying.
Backward - The last fixation point is movable/editable only. The first fixation point will not move if you are trying.

Easting and Northing

Only available for horizontal geometry.

These are the coordinates for placing the element.

The Easting and Northing coordinates are grouped for point 1 and point 2 and give the coordinates for the fixation of the elements.

Chainage and Elevation

Only available for vertical geometry.

The values for Chainage and Elevation are grouped in points 1 and 2 and gives the chainage and elevation of the fixation points.

Next topic: Calculation Error - Color-Coding