A civil expression that provides offset values (at the start and end) for an offset string derived from a corridor or linear template string - e.g., EOP (Edge of Pavement) is needed.

Currently, civil expressions only support offsets relative to a reference alignment, using syntax such as: CivilExpression.OffsetStart(this["Alignment Name - Ref Alg"]).

The proposed new functionality would streamline the creation of set back metadata for safety barrier strings, such as the face of a barrier designed as an offset string. Set back for safety barriers is one of the mandatory parameters required in technical specifications and in BIM models.