Topic: UN-CIVIL3d Corridor Models

[mjfarrell]

Is it only me, or has anyone else experienced the following failure with C3D corridor models.
The corridor fails to model certain real world conditions, like when your roadway centerline has curves or reverse curves?  I have been struggling for several days to properly model a particular corridor. The failure occurs each time the corridor enters the curve clockwise.  Reversing the alignments and modeling the road backwards produces acceptable results up to and until the alignment enters a tangents section (change in direction) at which point the corridor fails to hold the proper vertical alignment (slams to elevation ZERO, or worse introduces a random 30' increase in the vertical).  However IF we limit the model to segments that have NO change in alignment direction, and or reverse alignments to proceed counterclockwise, then the corridor model works.  As one might guess this is highly undesirable, and not what one would expect from autodesk's flagship civil design product.  Understand that these failures appear to occur only when attempting to model corridors with medians, and once the error appears all bets are off in terms of wether it holds ones vertical alignment or not. This result also happens with any number of variations in creating the assemblies being applied to the corridor.

[b_hailey]

I would love to take a look at that drawing.  Any chance you could e-mail it to me?

brianh at ctcivil dot com

[mjfarrell]

First, I may need permission to send the data to you, as it belongs to a client.  He is monitoring this post, so Gary if you see this perhaps you will post one one  those problem drawings.
Secondly I believe that if you try it yourself, by building a roadway with lanes away from median, and project 2% through the sloped median, and 2% on the roadways, the after you build the corridor, and the surface to go with it, that the median slope is not projected correctly to the center of the medians as they reduce towards the turn lanes, and the lanes away do not maintain 2% cross slope.

[mjfarrell]

This is some of the data.

The median appears to behave even worse in 2008.
You can switch alignments that the offsets are attached to and it will model the right or the left pavement section, on not both.

[Jeff_M]

Man, all the fun stuff gets posted when I don't have C3D available.....

Hopefully you leave that drawing there until I can snag it in the morning so I can have a looksee.

[mjfarrell]

Dang, I thought I had it working a moment ago, but no such luck.  Most frustrating; as the client has said that they did get some assemblies to work on this thing properly, with 2007.  Only they have not sent me a copy of the solution set.  So they did learn something, and now I need to teach myself that lesson somehow?

Oddly enough the failures in 2008 aren't even the same as the 07 ones? ! ?  :ugly:

If anyone out the is listening, or knows someone that will:

Please recode the median object

Of further interest, look at the surface that it is creating in the Corridor Region that is working. And I use that term very generously.  And I can post other corridor models that do work, which is even weirder.
Let me see about offering up an 07 data set.

[Dinosaur]

I would give it a try, but I am still version challenged and can only view the drawing with my 2007.  Is there any way to get 2007 compatible data or an xml?

[mjfarrell]

And now it has morphed out...and returns very odd results, with little or no regard for the actual assembly being appied.

[Jeff_M]

Well, I have it working/looking much better than it did, but I haven't, yet, gotten the right side X-slope to be maintained to the median curb. Using the technique described by Scott McEachron in THIS BLOG POST I was able to get the result shown in the picture.

I'm leaving in just a few minutes for a concert and won't return until sometime tomorrow. I'll have some time to play with this tonight, but no internet access will keep me from posting anything more until tomorrow.

[Jeff_M]

And the trick to get it to show the contours correctly is to create the surface from Featurelines, not the Links. This is in no way fine tuned, nor did I try to use the same curbs. I just grabbed stock Subassemblies to create  new assemblies. But the revised drawing should get you headed in the right direction.

Jeff

[mjfarrell]

Jeff,

Thanks for the post.  I went back to Remedial Corridor classes most of the weekend.

The rule I was attempting to break:

The Marked Point must be a part of the same Assembly Group, or Offset Group.
Objects will not find the Marked Point, if it isn't in the same offset group, and defined
in the assembly higher than the object looking for it. (The marked point that is).

I will probably post a copy of the 'solved' corridor later.  After watching a lot of videos, I've used a similar but different assembly than yours.  Mostly because a close inspection of your corridor showed that it was only modeling the left half of any portion of the median, even though the feature lines surface made it appear to be creating both sides correctly. 


The bigger lesson learned was that I was fighting with the corridor object, and using OFFSETS to do what should have been done using 'dummy' links to attach subassemblies to.

[sinc]

I find it somewhat comforting that this stuff still throws you, too.  That means I don't feel so bad when I have a hard time figuring out why my corridor doesn't model the way I expect.   

Now if we can just convince Autodesk that when we complain something is "too complicated", that doesn't mean "strip some things out and provide fewer features"...