After making certain types of changes to a corridor, you need rebuild the corridor.
Rebuilding a corridor updates it to apply all changes made to the corridor’s dependent components, such as its baselines, profiles, or dependent surfaces.
Corridors that need to be rebuilt have a warning icon
displayed next to the corridor’s name in the Prospector tree.
If corridor regions are locked to geometry, when the baseline alignment geometry is edited, only the regions that have been directly affected by the edits are rebuilt. For more information, see Specifying Corridor Region Lock Options.
In AutoCAD Civil 3D, you can rebuild a corridor manually, or set the corridor to rebuild automatically.
You can manually rebuild a selected corridor, or rebuild all corridors in the drawing.

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