Corridor Intersections "by hand"

[PEGAdevelopment]

I've heard from alot of people that the intersection tool is really buggy and doesn't do what you need it to; meaning that I will have to do my intersections "by hand".

 

Can I get a few pointers/steps on how this is done exactly. Thanks all.

[Organic]

It is done the same way in all civil design packages.

 

- First step is to layout the horizontal geometry, so the road centrelines and kerb lines (commonly called kerb returns).

- Then design the vertical geometry for the centreline alignments. Where the centrelines cross the elevation on the two profiles obviously has to be the same.

- Then create alignments and design the vertical geometry for each of the kerb returns. The start and end elevations need to tie in with the respective crossfall from the centrelines of the respective roads. You also need to ensure water will flow around the kerb line (1% fall etc).

- So once this is all done and you have a design that works (easier said than done), then you have 3d points for all aspects of the intersection. It is then just a matter of creating a surface from those points and contouring it. Then checking that the contours are what you expected and tweaking the design and updating the surface as required.

 

In Civil 3D you could use feature lines instead of alignments and profiles for the kerb return lines.

 

If you're designing a roundabout it is the same process except you'd have an extra alignment representing the centre island (bottom of concrete lip etc) and it will be a bit harder to design the vertical geometry to ensure appropriate crossfalls and drainage is maintained all around the roundabout.

[Bill_Myron]

http://civilforautocad.blogspot.ca/2009/03/pre-2010-intersection-design-with-civil.html