topic Re: Corridor surface problems through intersection in Civil 3D Forum

Corridor surface problems through intersection

alex_georgevitch — Wed, 12 Jan 2022 18:15:52 GMT

I am working on a large corridor (about 2 miles) with several intersections and different sections. I would call it a complex corridor. For the most part everything is performing well and I am using the latest build of Civil 3D 2022. All the intersections are created manually using targets and several assemblies.

The problem I am having is occurring on the main line through the intersection. Several (but not all) of the intersections have strange anomalies with contours in the middle of the intersection. The assembly through the middle of the intersection is very basic and often is just two subassemblies (LaneSuperelevationAOR left and right). The subassembly has a 2% cross slope and no supers through the intersections. The edge of travelway is being extracted and used for a target for the curb returns outside of the main corridor. Here is what I would expect for the mainline through the intersection:

The above intersection gives a very nice "v" contour and has no change until after the edge of travelway.

Here is a small anomoly:

And then here are a few intersections that get worst:

Everything circled in yellow is confusing me and I have no idea how a constant 2% cross slope on a corridor can be influenced by things beyond the edge of the corridor. These are small anomalies and when I turn on points and tin lines for the top surface I can only see a few tenths of a foot in the worst locations.

If anyone has any insight as to why this would be happening I would really appreciate it. I cannot rebuild the corridor as it has been in design for almost 2 years and we are just finishing up the project on a tight timeline. Unfortunately, we need to provide a finish surface to contractors to bid the project and I want to get it as "right" as possible. Thanks in advance and let me know if there is any other info I can provide.

Re: Corridor surface problems through intersection

rl_jackson — Wed, 12 Jan 2022 19:45:24 GMT

Just from what I looked at there appears to be an issue with the underling linework being on the same SITE as the FG surface. It could be that you just need to change the SITE for the FG or the underline linework that is jacking up your FG surface.

Re: Corridor surface problems through intersection

user181 — Wed, 12 Jan 2022 20:15:18 GMT

How did you create the surface? Did you use top links and select top links for overhang correction? Or did you add a bunch of other links and breaklines?

Re: Corridor surface problems through intersection

alex_georgevitch — Thu, 13 Jan 2022 06:06:54 GMT

Yes, Top Links:

Re: Corridor surface problems through intersection

alex_georgevitch — Thu, 13 Jan 2022 06:09:05 GMT

Rick, not exactly sure what you meant by this response. The surface is being created by the corridor, no site used. The underlying linework is there to for reference only (they are actually xrefs) to aid in design work. Let me know if I am missing something please and thanks for your response.