2.0

Working with the Vertical Alignment Tangents for the Finished Ground Centerline
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3 Select the starting point using one of the following methods:
n
Select a point from the drawing. You are prompted for the station and
elevation. The default station is the station of the point selected. The default
elevation is the elevation of the point selected.
n
Type S to select a station.
You are prompted for the station and elevation. The default for the station is
the starting station of the profile. The default elevation is the elevation of
the existing ground at the station entered.
4 Enter a station and elevation for the starting point of the tangent, or press
ENTER to accept the default values.
5 Select a point to end the tangent using one of the following methods:
n
Select a point in the drawing.
n
Type L to specify a length. The command prompts you to select a grade,
elevation, or point to define the elevation of the endpoint of the tangent:
Grade: The grade option calculates the endpoint of the tangent using the
station defined at the previous prompt and an entered grade. Enter the grade
in percent. A positive value indicates a tangent going up; and a negative
value indicates a tangent going down.
Elevation: The elevation option calculates the endpoint of the tangent using
the station defined at the previous prompt and an entered elevation. Enter
the elevation for the endpoint of the tangent.
Point: Selecting a point at this prompt causes the command to use the
elevation of the point selected to determine the endpoint of the tangent.
n
Type S to enter a station. The command prompts you to select a grade,
elevation, or point to define the elevation of the endpoint of the tangent.
NOTE
Type
U
to erase the previous line drawn and revert to the previous station
and elevation entered. Type
X
to exit the command.
After displaying the station, elevation, and last grade of the current point, the
command prompts for another length, station, or point.
6 Press ENTER to end the command.
The following illustration shows some of the parameters used in creating
vertical alignment tangents:
Parameters in a vertical alignment tangent