Question:
I used Automated Superelevation tool (Autoshape) to generate these shapes. What causes the errors to shown in
the areas of the reverse curves (curves L-4 & L-5 and L-12 & L-13).
Answer:
Upon describing COGO chain -L-, there is a 0.0001' tangent section near the PRC.
This can cause Geopak to process the Autoshape input file incorrectly.
Restoring the same chain without a small tangent section at the PRC produces a normal set of Geopak shapes.
Note that this is not a problem with the superelevation tables or preferences. Since it is the same
Autoshape input file that is processed, the only difference was the COGO chain, it would indicate Geopak having
issues with a small tangent section near the PRC in a reverse curve configuration.
NC DOT
NC DOH
NC GOV
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