To change the radius of a horizontal curve

You can select the radius from a range of values, or drag the curve points of tangency or midpoint manipulators.

To select the radius from a range of values

1. Click Edit.
2. Select the road.
3. Right-click the curve you want to change. Highlight Edit Curve.
   
4. Change the radius in either of the following ways:
   • Drag the slider to the desired radius.
   • Enter a value in the Curve Radius cell.
   Note: The radius values that are geometrically possible for the curve are shown on the continuum. If a value that is outside the solvable range is entered, a warning message is displayed.

To drag the curve manipulators to adjust the radius

1. Click Edit.
2. Select the road.
3. Drag either of these manipulators, as shown, to change the curve radius.
   
   

   Alternatively, you can enter a radius value in the toolbar.

   Note: Curve manipulators are not available for spiral curve spiral groups.