PositioningElement which provides a Linear Referencing System for locating PhysicalElements. An Alignment shall be continuous, non-branching, and non-overlapping. If it is a Project Alignment, it is for a single alternative, as specified by its owning ProjectPart.
combined horizontal and vertical alignment represented as a 3D linestring. If an Alignment also has a HorizontalAlignment and VerticalAlignment, the 3DAlignment must agree in geometry. In this case, it was probably generated from the HorizontalAlignment and VerticalAlignments.
part of a horizontal alignment having a single geometric representation (either line, circular curve, clothoid, or other spiral)
long section profile along a line at or offset from a horizontal alignment. 2D coordinate axes are alignment distanceAlong and ground elevation. State distinguishes between existing ground surface vs. proposed design profile.