To Place Referenceline by Midpoint

To place a referenceline centered on the active alignment, use the following procedure.

You must have an active tunnel unit and alignment to place a referenceline.

The length, location (station), and orientation (skew) of the referenceline must be specified.

Either: On the Home ribbon tab, select the Place>Middle tool in the Reference Line group.

Or

Key in TDGEOMETRY REFERENCE MIDDLE
In the Place ReferenceLine By Midpoit tool settings dialog:
1. Type the Skew Angle value if not normal to the alignment.
2. Type supportline Length.
  Note: If you do not specify a length, then the distance away from the alignment where you data point will be taken as half the supportline length.
3. Type the Station.
  Note: If you do not specify a station, then the point on the alignment closes to where you data point will be taken as the station.
(Optional) Select a Direction Mode and Feature Definition.
In the view window:
1. Data point to accept the station. Data point again to accept the length. If you did not specify a Length and Station in the tool settings, your data point will determine these values.
  Tip: The tool gives you a dynamic preview of the referenceline with the current tool settings and mouse pointer location (if some tool settings are not locked).
  
  The referenceline is placed.