Roadway Design Question and Answer Forum
Criteria
Question:
I am working on a project with a 23' median and with some superstreet designs. There are some sections where
the inside left turn lane crosses over the center line. Why doesn't' the GGC Automatic Pavement Extension
(APE) work for these sections?
Answer:
Here is the current default behavior of GGC APE for automatic pavement extension inside the median.
1. Determine the location of the GGC APE blue line, left or right side of the centerline.
2. Determine the location of the inside EOT within that side of the median.
3. If an EOT line is located within that side of the median, then extend pavement there.
4. If an EOT line is NOT located within that side of the median, then extend pavement to the centerline.
For most superstreet designs when left turn lanes are on the other side of the centerline, #2 could not be
established. Current Criteria does not have the "intelligence" built-in to achieve the desired result.
Modification to Criteria behavior #2 yields the desired result and should fix this issue.
1. Determine the location of the GGC APE blue line, left or right side of the centerline.
2. Determine the location of the inside EOT within the median (both sides).
3. If an EOT line is located within the median, then extend pavement there.
4. If an EOT line is NOT located within the median, then extend pavement to the centerline.
Because Criteria will always first check for the GGC APE blue line location (#1), a clear-cut instruction to
Criteria is given to what side to start the pavement extension from. Below is a typical application of GGC
APE and at superstreet intersections.
