Exercise 4: Adding and Modifying Superelevation Chainages

In this exercise, you will resolve overlap between two superelevated curves by adding and removing critical chainages, and then editing existing superelevation data.

This exercise continues from Exercise 3: Creating a Superelevation View.

Examine the superelevation parameters

1. Open Align-Superelevation-4.dwg, which is located in the tutorials drawings folder.
2. In the top viewport, zoom in to the middle of the superelevation view.

   Near chainage 0+558.66, the indicates that the two curves overlap. At the bottom of the superelevation view, the light blue and red lines, which represent the left and right shoulders, cross over each other.

3. In the superelevation view, select one of the lines.
4. Right-click. Click Open Tabular Editor.
5. In the Superelevation Tabular Editor, scroll down to Curve.3.

   In the Overlap column, two rows display . This icon indicates that the superelevation stations of two or more critical chainages overlap. In this case, chainage value for the last critical chainage of Curve.2 is greater than the chainage value for the first critical chainage of Curve.3.

6. Under Curve.3, under Transition In Region, select the End Normal Shoulder row.

   The curve is highlighted in the bottom viewport, and the critical chainage is marked with a blue tick.

7. In the Overlap column, click .

   The Superelevation - Overlap Detected dialog box presents two options:

   • Automatically Resolve Overlap —This option removes the overlapping critical chainages of the affected curves.
   • Ignore Overlap—This option enables you to return to the Superelevation Tabular Editor to manually modify the data. The icons are not cleared.
8. In the Superelevation - Overlap Detected dialog box, click Ignore Overlap.

Edit superelevation chainages

1. In the Superelevation Tabular Editor, under Curve.2Transition Out Region, select the Begin Normal Shoulder row.
2. Change the Start Chainage value to 0+560.00.

Remove a superelevation critical chainage

1. In the Superelevation Tabular Editor, under Curve.3Transition In Region, select the End Normal Shoulder row.
2. Click .

   The End Normal Shoulder superelevation critical chainage is removed.

Add a superelevation critical chainage

1. In the Superelevation Tabular Editor, select the Curve.3 row.
2. Click .

   The Superelevation Tabular Editor is hidden, and you are prompted to specify a chainage along the alignment.

3. On the command line, enter 568. Press Enter.

   A new manual chainage, which starts at chainage 0+568.00, is displayed in the Superelevation Tabular Editor.

4. Right-click the Manual Chainage. Click Assign Critical ChainageEnd Normal Shoulder.
5. In the End Normal Shoulder row, enter the following values:
   Note:

   The remaining columns are interpreted from these values.

   • Left Outside Shoulder: -5.00%
   • Left Outside Lane: -2.00%
   • Right Outside Lane: -2.00%
   • Right Outside Shoulder: -5.00%
   Note:

   To import existing superelevation data from a CSV file, click .

   Notice that the icons are no longer displayed in the Overlap column.

6. Click to close the Superelevation Tabular Editor.

To continue this tutorial, go to Exercise 5: Editing Superelevation Parameters Graphically.