Create a roundabouts

I am trying to create a roundabout using the civil cells. However after going through the process of selecting the primary and secondary alignments, the cell  and associated corridor and alignments are generated miles away from the intended location.

  • This can happen when the approach geometry is severe. Some examples I have seen this occur are:

    • The approach alignment has curvature very close the the circle.
    • The radius of the circle is relatively small

    In both cases, what happens is that the radii from the approach to the circle cannot solve or solves in unexpected ways, such as solving in a different quadrant. In such cases most of the approach looks OK but a handful of the radii near the circle will be miles away.

    If this matches your problem then the only solution I know is to drop the civil cell, delete the offending bits and rebuild them using the geometry tools.

    Robert Garrett
    Senior Consultant

    www.envisioncad.com