About Alignment Widenings

You can apply widening for a specified length along an alignment.

Each widening includes transition regions at the entry and the exit. In the figure, region 1 is the entry transition, and region 3 is the exit transition, based on the direction of the centerline alignment. Default values for the length and shape of these transitions are determined by command settings for the AddWidening command.

The transitions extend forward and back from the specified widening start and end chainages. In the example shown, the widening starts at chainage 3+00 and the transition length is 75, so the entry transition starts at 2+25.

Corner radius alignments in junctions can be edited to add widenings at one or both ends. This type of widening typically forms a turning lane at the entry to a corner radius or a merge lane at the exit from a corner radius.

You can also add automatic widening to dynamic offset alignments.

Note: You can add a widening to any alignment type except Rail alignments. Widening can be added to another widening.

In the command settings for alignment commands, you can configure a variety of options to control default behavior for how widenings and tapers are created in widening situations. For example, on the AddWidening command, you can configure the default settings for how the Linear Taper Around Curves option creates linear tapers in widening situations. For more information, see Edit Feature Settings - Alignment dialog box.