Conduit

Merriam-Webster’s online dictionary defines a “conduit” as:

1: a natural or artificial channel through which something (such as a fluid) is conveyed

For our purposes, we consider the flow of traffic. A Conduit represents a regulated flow of traffic in a single direction.

The established term “carriageway” is somewhat synonymous, but only in cases where a Conduit is bounded by physical barriers. On a Road Segment with a single painted line separating opposing traffic, there is no established term to refer to a set of Lanes flowing traffic in the same direction.

So a Conduit is, in fact, a superset of what “carriageway” appears to define.

Identifiers

1. Road segment + Role

Since no more than one type of Conduit may be present in a Road Segment, we can use the Road Segment.ID in conjunction with the Conduit.Role to distinguish one Conduit from another

Attributes

Role

Given some Road Segment, a given Conduit must be forward, reverse or unpaired (in the case of a One Way Road Segment). We get conclusion simply by taking the union of the subclass names.

Thus we can talk about RS1-F (the forward Conduit in Road Segment RS1, for example.

Type: [ F | R | U ] forward, reverse or unpaired