Identifying Site Regions, Problems Around Arcs

I am working on assigning Site Regions to my project. The areas around the bull nose on the curbs are causing my Light Duty and Heavy Duty Pavements to not be assigned correctly. I have attached two screenshots, which I hope help further explain this. The first screen shot is the line work. All lines are touching and or closed, via trim/extend. The second screen shot shows what happens when I try to assign the Site Region. I think it has something to do with the arc, when zoomed in, while on the Identify Site Regions Command, it shows more of a segments arc, rather than a smooth line. Is there a way to clean this up?



The best way to handle this is to break the arc at the point where it intersects with the line and then join it back together again. This forces the TIN model to create a node at the intersection of the two lines which forces the two lines to close correctly and form the SI Areas correctly.

The issue is caused by the triangulation of a curved line - it is subdivided into arcs based on your breakline approximation parameters and those can fall either side of the line that is intersecting the arc - this means that the TIN is actually inside the arc and that there is a small gap between the surface created from the arc and the intersecting line - this allows the SI to leak out of the area.

You can also increase the gap closure tolerance setting for gaps - that may also help solve the issue - however when I see these types of things I typically either add a VPI or 3D node on the ARC at the point where the lines intersect - that way there is a 3D node at the location, or I break the arc and rejoin it at that location which causes a 3D node to be formed at that point also. (Project Settings - Computations - Takeoff - Gap Closure Tolerance).


Let me know if that helps