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Chapter 3 Working with Profiles and Vertical Alignments
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4 You can edit the following vertical curve parameters:
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Type a Curve Length to define the distance between the PVC (Point of
Vertical Curvature) and the PVT (Point of Vertical Tangency).
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Type a K Value to define the K value of a vertical curve is the horizontal
distance required to effect a 1% change in grade on the vertical curve. (K =
Length of curve / (|Grade in| - |Grade out|). |X| refers to Absolute Value.
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Type a High Point Elevation to define the elevation of the highest point on a
crest vertical curve.
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Type a High Point Station to define the station of the highest point on a
crest vertical curve.
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Type a Low Point Elevation to define the elevation of the lowest point on a
sag vertical curve.
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Type a Low Point Station to define the station of the lowest point on a sag
vertical curve.
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Type a Passing Sight Distance to define the distance measured to a point
where an approaching vehicle comes into view ahead of a driver on an
undivided road. This is used to calculate crest vertical curves.
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Type a Stopping Sight Distance to define the distance measured to a point
where an object comes into view requiring the driver to stop. This value is
used to calculate crest vertical curves.
Not all of these options are available for each type of vertical curve box. All
vertical curve variables are interrelated, therefore, any edits you make to the
curve data automatically update any corresponding curve data. Use Next and
Prev to navigate from curve to curve.
5 Click OK to return to the Vertical Alignment Editor and save the edits.
Copying the Vertical Alignment Surfaces with
the Vertical Alignment Editor
To save time creating vertical alignment data, you can use the Vertical
Alignment Editor to copy the data from one vertical alignment to another, and
then edit that copy.
To copy a vertical alignment surface to another surface or vertical alignment
1 Display the Vertical Alignment Editor dialog box in one of the following ways:
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From the Profiles menu, choose FG Vertical Alignments
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Edit.
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From the Profiles menu, choose DT Vertical Alignments
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Edit.
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From the Profiles menu, choose Existing Ground
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Edit Vertical Alignment.
2 From the Vert. Alignment list, select the alignment to copy.
3 Click Copy Surf to display the Copy Surface dialog box.
4 Using the To Surface list, set the surface to copy the current surface.
The From Surface label shows the current surface or vertical alignment selected.
5 Click OK to copy the surface.