Purpose: Used to define girder spans in parallel/concentric geometry Girder System Projects. (SPN data is generated in girder input in Girder System Projects from SPN-1 data in girder system input. See SPN also for Line Girder Projects.)
--> Given in girder system input
SPN-1 is a list of spans between bearing locations (feet or meters) for Girder 1, the rightmost girder, beginning from the left bearing of this girder. Spans are measured along horizontal curvature, if present. There is a 20 span limit.
Span Lengths of Girder 1 in Parallel/Concentric Girder System Projects