To Add Spiral-Curve-Spiral Groups To Alignments

  1. Click the alignment. Click Alignment tabModify panelGeometry Editor.
  2. On the Alignment Layout Tools toolbar, click Free Spiral-Curve-Spiral (Between Two Entities).
  3. Select the entity from which you want to add the spiral-curve-spiral.
  4. Select the entity to which you want to add the spiral-curve-spiral.
  5. Select the spiral-in length by picking two points in the drawing or by entering a spiral-in A value.

    Specify a new value, or press Enter to accept the value that is displayed on the command line.

    • If the alignment has design criteria applied to it, the minimum value for the current design speed is displayed.
    • If the alignment does not have design criteria applied to it, the default value specified in the curve and spiral settings is displayed.
  6. Select the spiral-out length or enter a spiral-out A value.
  7. Specify whether the curve solution angle is either greater than or less than 180 degrees.
  8. Specify a radius by either entering value or selecting two points in the drawing. Or, enter D to specify the degree of curvature

    To display a curve preview you must either pick a point in the drawing or enter a coordinate value. Then, rubber band is drawn to the cursor from the selected point and the curve preview is displayed.

    Note: To calculate the radius or degree of curvature using other known curve parameters, enter 'CCALC to open the Curve Calculator.
    Note: If you enter an A value for either the spiral-in or the spiral-out value, then the curve preview is not displayed when you specify the radius.