Transitions Between Assemblies

[doni49]

Hi All!

I did a search on this topic and from what I've read, it sounds like the transition should happen automatically (although some tweaking may be required).

But for some reason, I'm NOT getting a transition.

I had one assembly for the entire length and the designer wanted to have the curb stop at 0+40 and from 0+40 to the end, he wanted NO CURB--just an EOP.

So I copied the assembly, modified the copy so that there was no longer a curb and attached the shoulder (that was previously connected to the curb) to the EOP.

So the codes should all be same.

EDIT:  I just attached a dwg file (created/saved in 2012) with my two assemblies in it.  Can anyone see any reason for this? 

Here's a screen shot of what I'm getting:

 

[doni49]

It just went from bad to worse.  😞

At the other end of the project, I need to transtion from normal crown roadway at 21+00 to FLAT roadway at 21+38.

I copied the Normal Crown assembly and changed the cross slopes to 0%.  I split my corridor.

One region uses Normal Crown assembly up to 21+00.  The other region uses FLAT ROADWAY assembly beginning at 21+38.  I need to get the EOP/shoulder lines etc to transion between these two stations.

[doni49]

I've continued to search and I've found lots of places that say it should happen automatically.  THen I've found lots of places that say it can't be done.

One alternative that I found which looks reasonable is to use feature lines to connect the features between the two assemblies and then create an assembly for use in this region which targets the feature lines.

http://forums.autodesk.com/t5/AutoCAD-Civil-3D/Transitioning-between-asseblies-of-varying-cross-slop...

So I have two questions about this idea.

1. Is there a way to tie the feature lines directly to the points in the assemblies so that if/when the corridor changes, the feature ines also adjust accordingly (and allow this region to update as well)?
2. I spent the better part of an hour yesterday afternoon trying to figure out which subassemblies to use in the new assembly.  Any pointers?

EDIT:  I guess that if I can get the feature lines to automatically update as the corridor changes and I can also get those feature lines to be part of the surface, then I don't really need to have an assembly that targets the feature lines.

[doni49]

Ok.  Now I've come across a message here in this forum that sounds like it shoud help.

The message:

http://forums.autodesk.com/t5/AutoCAD-Civil-3D/Transition-between-assemblies/m-p/2905978#M145372

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You can also achieve the transition by means of a featureline snapped to the ends of the assemblies on the ends of the transition. It can be a curved featureline or polyline, but a featureline should automatically adjust to the elevations of the corridor when edited. Use the featureline as a vertical target for the corridor assembly through the transition, making sure the assembly can follow a target.

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If the featureline has the proper vertical info and it updates automatically when the corridor changes, can't I just add the featureline to the surface?

[mathewkol]

1. Corridors never thansition automatically from one assembly to the next.
2. You're saying that you want the feature line to update when the corridor changes. It doesn't work that way. You edit the feature line, which is being targetted by the corridor, then rebuild the corridor. What happens is the corridor updates when the feature line is edited.

Your scenario where the road changes from 2 percent to flat is more efficiently accomplished with a single region/assembly ans by using superelevation. You need to use a subassembly which us compatible with superelevation. Such as lane-something-AOR (in 2013).

[mathewkol]

When iyou are asking about transitioning, I wonder if you have the correct terminology. I'm looking at your image and I think this is plan view? The crown is connected but the rest do not. Is this what you mean by not transitioning?

If they are not connecting, it's often unimportant as the surface generally builds correctly anyway.

[doni49]

Yes it's plan view. And although the surface DOES look correct in the first situation I asked about (where it goes from curb to no curb), the plan shows a gap in the EOP & shoulder lines.

You noted that the crown is connecting. No it's not - - that's the baseline.

And the second area surface is NOT getting the surface between the regions. Notice what the contours look like? I'll investigate using superelevation on this.

[doni49]

Also if not transition, what would you call it?

I'm new to C3D and used to use InRoads. It WAS called transition in that program and if you had one region assigned to one assembly and the next region assigned to a different assembly, it would attempt to connect the two if both had points of the same code.

And it even had a "Transition Editor" that would show me all the point from both assembly drops and allow me to say "connect this point to this point" or even "connect these points to this point". Such as going from having a ditch to no ditch.

If the ditch ended at 11+00, I would drop the next assembly at 11+05. The gap would be controlled via the transition editor. Connect the ditch foreslope & backslope @ 11+00 to the daylight point @11+05.

[mathewkol]

Well, we don't have a transition editor.  Usually we would just start the next assembly at the same station where the previous one ends, unlike yours where you have a gap.  Feature lines do not connect across a gap, like you have.  For your scenario, I don't see any need for a gap, but even as you have one, you said the surface appears to be ok and that's the important thing.  Having a gap in the corridor is generally fine, except for ta few circumstances.

I looked at your drawing, and you won't be able to use superelevatio nwith the basic subassemblies.  You'l need the LaneSuperelevationAOR.

[fcernst]

So I copied the assembly, modified the copy so that there was no longer a curb and attached the shoulder (that was previously connected to the curb) to the EOP.

Don't do this. Use Conditional subassemblies with one master Assembly to make subassemblies appear and disappear as desired...

[doni49]

Thank you both for your advice.  Please don't take anything in this message as me trying to convince you that I'm right -- as that's DEFINITELY not the case.  I'm trying to make sure I understand how to use this program to its fullest potential.  My boss has me scheduled for an actual training class in May.  But that's the earliest availability they have and in the meantime, I'm trying to do the best I can to do what I need to get done.

It sounds like you're both saying I should use one assembly for my entire corridor if I want the corridor to automatically draw the feature lines and correctly do the volume calcs.

In the case of the first issue I asked about (where I was going from curb to no curb), I can't really have two assemblies at the same station--one showing curb and the other showing no curb.  That causes the contours to make a real mess.  one assembly wants the FG to be higher than the other assembly at the same station.  How can that be a good thing?

At my previous job, I used InRoads with MicroStation and I worked on a massive project that included 5 miles of highway in which the NJ Turnpike was being widened from a divided highway with 3 lanes in each direction to a bifurcated highway with 6 lanes in each direction and a BUNCH of different end conditions.  If I had to do that with ONE assembly that contained every possible end condition, I can only imagine how difficult it would be to manage.

[doni49]

I realized something late last night about the NJ Turnpike scenario that I mentioned.  I hated the fact that every some minute detail changed, I had to create a whole new template (that's what InRoads calls them--Civil 3D calls them Assemblies).  There were many times that I would LOVE to have been able to make my change and have the rest of the template continue on.  And I think that having it all in one Assembly will allow for that.

Thanks for all the advice!

[Neilw_05]

Matt is right, the featureline elevations will not dynamically update when the corridor is edited as I stated in the thread you cited. Featureline behavior is different when used with corridors vs. gradings. You'd have to manually edit the featureline to update the corridor.

You mention how InRoads automatically links like codes across transitions. Civil 3D used to do that but it was disabled in 2011 for reasons I don't know. Currently there is no built-in provision for transitions in the software, so we are left to ourselves to come up with workarounds.

You wondered about adding featurelines to the corridor surface. You can do that but you won't have subsurface materials in the volume calcs or corridor components in the cross sections in those areas.

I'm not an InRoads user but I know there are ways to configure it's templates to respond to variable conditions (which is what C3D conditional assemblies are for). From what I've seen in demos and videos I've always believed their templates could do everything C3D can and more.

[doni49]

I've already fixed the first issue that I asked about. I created offset alignments where I need curb. Then I changed the assembly so that it uses a ConditionalHorizontalTarget. If it finds the offset alignment, it draws the curb then the slope. If it doesn't find the offset alignment, it draws the slope without curb.

Worked well.


Now I'm having trouble with the other area. I tried using Superelevation as suggested but every time I click finish, it crashes.

I gave up on that and I'm attempting to create a sub assembly that will target the offset alignment. If it finds the offset alignment, draw the lane at 0%. If it doesn't find it, draw the lane at 2%.

[Neilw_05]

I've experimented with a technique that allows you to apply different regions and assemblies independently to the edges of the lanes rather than working from the centerline outward. It provides much more control for varying conditions across the roadway and along the edges without having to create numerous conditional branches on your assemblies.

I've not used it enough to say it doesn't have any issues but it might be worth considering in cases where things get too messy using the traditional approach.

Here is a link to the topic: http://forums.autodesk.com/t5/AutoCAD-Civil-3D/How-to-model-corridor-from-edge-toward-centerline/td-.... The latter part of the thread is the most relevant.

[joantopo]

I think that the best way to make a transition ditch is using a custom subassemby with SAC with methods BaseLine.StartStation and BaseLineEndStation.
If the ditch has 3 slopes, always use (delta x and delta y to define them)
For example, if it is a ditch on the right side, then in the baseLine.EndStation the delta x is 0 for the 3 slopes.
However, you cannot add a frequency in this region, only sample the start and end of thr region because the ditch could be in the curve of the alignment and your transition is linear.

You create a new assembly with that subassembly and put that assembly in a region between them.

In fact, I would like that C3D had the transitions as InRoads as you mention.