Intersections as seperate corridors

[Neilw_05]

What is the advantage of creating a seperate corridor for an intersection? Doing so requires leaving gaps in the road corridors at the intersections which creates a mess in the surface triangulation through the gap. I know we can clean it up by creating a composite surface and pasting all the pieces together but how tediious that is!

I was wanting to keep the intersections as seperate corridors because if we add them to the road corridor we end up with numerous duplicate baselines which makes editing and data management a nightmare.

This whole process is a huge time consumer. I can't understand how Autodesk expects DOT's to adopt this software with this workflow.

[sboon]

Using separate corridors allows you to assign the featurelines from one corridor as targets for another one.  I'm not sure that I understand your comment about gaps, all of the separate corridors can be adjusted so that they're touching each other - a good way to confirm that the top surfaces all match at the interfaces.

[Neilw_05]

Perhaps you didn't understand my post Steve. I'm talking about making each intersection an independent corridor from the road corridors (using that option in the wizard). Consider a long road with several side roads that intersect it. If each intersection is created as a seperate corridor you have to leave gaps in the crossing roads at the seams of the intersection corridors. Then when you create surfaces for the road corridors the triangulation forms across the gaps and have to be cleaned up somehow.

[sboon]

OK so you want one corridor per crossing roadway, with two regions and a gap.  There's a couple of solutions for this.  You can create two surfaces and then apply a different station range to the boundary feature lines for each one.  The boundary definition for surface 1 would be Daylight - Rt from start to the gap and then Daylight - Lt from the gap back to the start.  The other surface boundary would continue from the gap to the end of the road.  This method has the advantage of keeping all of the definiton work inside the corridor but you'll have to edit the boundaries manually if you do anything to the corridors.

The other method would be to have a single surface with a hide boundary across the intersection.  This method is nice because it's a graphic edit - you can move the boundary by dragging a polyline.

[neilyj666]

This is a useful discussion - I'm just doing fairly simple corridors/intersections for windfarm roads and have previously created corridors and intersection corridors as seperate objects. In the intersection I apply a null assembly but the surface (e.g. formation) spans across the gap and I tend to remove these lines manually. I then paste the surfaces together to get a composite formation surface.

I have this week created the corridor and added the intersection as a new baseline i.e. one corridor object - will the formation surface be formed correctly or will there be some manual tidying up??

[Neilw_05]

"The other method would be to have a single surface with a hide boundary across the intersection.  This method is nice because it's a graphic edit - you can move the boundary by dragging a polyline."

Actually your comment brings to mind the new capability to use an intersecting surface as a hide boundary. If it can be utilized then there would be no need to manage boundaries at all. Have you tried that Steve?

[sboon]

It will be a single surface and it will usually fill in any gaps between regions / baselines etc.  This scenario is the reason why Autodesk added the shrinkwrap option for corridor surfaces.  Normally I prefer to drag all of the region boundaries so that they almost touch, so that I can look at the top surface contours for any errors in crossfall etc.

[sboon]

If I recall correctly that option is only available in 2013.  I haven't tried it yet.

[Neilw_05]

You are dealing with this issue as well I see. If you choose to add the intersection to your road corridor then the surface will be properly formed through the intersection However you will then have all the intersection baselines added to your corridor. If you then want to add a corridor region (using the mouse popup menu) you will have to figure out which baseline is the one you want need to select. You could end up with several duplicate centerline baselines, one for each intersection and each with a meaningless default name. Thus you'll have to go through the corridor and rename the baselines to help distinguish them.

As you have found, if you create the intersections as seperate corridors you have to combine their surfaces into a composite to get a contiguous finished surface. Either way it's a pain.

[sboon]

Having two Neil's on this thread is giving me a headache - I have to keep going back and re-reading to figure out which Neil is answering which comment

[neilyj666]

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@sboon wrote:

Having two Neil's on this thread is giving me a headache - I have to keep going back and re-reading to figure out which Neil is answering which comment

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LOL.....

...@neilw - I suppose an advantage of having one mega-corridor is it makes extracting featurelines easier as well as applying style sets as there is only one object. I did think that the Object view was much faster with one big corridor rather than several smaller ones.