Exercise 3: Adding a Turn Slip Lane to a Roundabout

In this exercise, you create the geometry for a turn slip lane, which allows vehicles to bypass the roundabout and turn from one approach road to another.

Select the entry and exit approach roads

  1. Open Roundabout-Slip Lane-Add.dwg, which is located in the tutorials drawings folder.
  2. Click Home tab Create Design panel Intersections drop-down Add Turn Slip Lane.
  3. For the Entry Approach road, click the Approach_SN (1) alignment.
  4. For the Exit Approach road, click the Approach_EW alignment.

Specify the slip lane parameters

  1. In the Draw Slip Lane dialog box, under Slip Lane Parameters, specify the following parameters:
    • Segmentation Line Length: 1
    • Length of Deceleration Lane: 20
    • Length of Acceleration Lane: 10
    • Lane Width: 4
    • Radius: 50
    • Taper Length: 20
  2. Under Draw Pavement Markings, specify the following parameters:
    • Outer Edge: Selected; Continuous
    • Decelerating Transition Line: Cleared
    • Accelerating Transition Line: Cleared
  3. Specify the alignment properties:
    • Alignment Style: Roundabout - Slip Lane
    • Alignment Layer: 0
    • Alignment Label Set: Roundabout - Slip Lane
    • Alignment Name Prefix: SlipLane
  4. Click OK.

    The slip lane is displayed in the drawing.

To continue this tutorial, go to Exercise 4: Editing Roundabout Components.