Alignment offsets

Alignment offsets are typically used at horizontal curves in a rail tunnel to ensure that carriage clearance is maintained when the track is rotated. However, they can be used anywhere along the tunnel alignment provided there is a valid horizontal alignment, vertical alignment, and template assigned.

The following diagram illustrates using alignment offsets to avoid carriage conflict with the design tunnel.

1 Horizontal offset 4 Offset tunnel
2 Vertical offset 5 Design tunnel
3 Carriage conflict    

To add alignment offsets to the tunnel definition, see To add alignment offsets.