Is there a median that works just like LaneSuperelevationAOR?

[soonhui]

I have a LaneSuperelevationAOR, but with median standing in the middle. The behavior of the median is just as if  it's a full lane across. 

I could have modelled everything as LaneSuperelevationAOR for both left and right lane, but I feel like I need to have median subassemblies right in the middle for clarity. Is there a median subassembly that

1. Assumes a slope that is like the connecting LaneSuperelevationAOR. 
2. rotates also like LaneSuperelevationAOR?

[ecfernandez]

Hi @soonhui, could you please explain your situation with a sketch? This is to better understand your problem

Regards! 

[soonhui]

@ecfernandez , an easy way to understand the issue is that I want to connect two LaneSuperelevationAOR side by side  ( but two LaneSuperelevationAOR  on the right side is not allowed in Civil 3D).

So for this configuration, what median subassembly I can use-- instead of the inner LaneSuperelevationAOR-- that could replicate this functionalities? 

[ecfernandez]

Hi @soonhui, you can alternatively use LinkWidthAndSlope or any of thefollowing median subassemblies

Lastly, the GenericPavementStructure subassembly seems to be a good fit too. What I like from this subassembly is that we can customize its point, link, and shape codes.

The median subassembly might not need to read the superelevation values since it could behave like a floating link between the elevations on the right and left road edge. However, is you really want this median subassembly to be able to read the superelevation, you should go with any of the following:

LinkWidthAndSlope or GenericPavementStructure.

MedianFlushWithBarrier. If you don't want it to show the barrier set the "Include barrier" fielt to "Ommit barrier"

Lastly, the MedianRaisedWithCrown also reads superelevation. You might want to try with this one too.

I hope any of these options help you. Best regards!

[soonhui]

@ecfernandez , let me go through one by one your suggestion:

1. LinkWidthAndSlope is not a 2D structure-- it's just a link, so how can it be used to construct a corridor with 3D profiles with cut and fill?
2. MedianFlushWithBarrier looks good, but then it only supports Pivot Method of Median Edges, which means flat median, and to be used on divided crowned roads. What about undivided crowned roads and I want the median to follow the superelevation of the lane?
3. MedianRaisedWithCrown -- for some reason I fail to construct it. It simply doesn't follow the Mark point that I assign to it. 
4. Generic Pavement Structure seems to be the only promising one. 

[ecfernandez]

Hi @soonhui, 

I have the following comments:

1.  LinkWidthAndSlope: Despite this subassembly being just a link, you can still compute cut/fill volumes. To compute those quantities, you just need a Datum surface and an EG surface. Since you can add the Datum code to the Link Code field of this subassembly, Civil 3D will create the surface on the area covered by the link, enabling volume computation.

It is not possible to compute pavement materials, such as a subbase or another granular material you may want to add to the median, with this subassembly. However, in my experience working with divided roads, I don't remember this being a serious limitation.

2. and 3. For an undivided road, I can't figure out where the median would go, so there is no need to worry about that. On the other hand, there is usually a way to make things work in Civil 3D. Indeed, these subassemblies can read the superelevation of the lane or shoulder and lane, respectively. So I bet you can harness that.

4. GenericPavementStructure: As its name says, this is a generic subassembly. Regardless of its name, I have often used it for things other than the pavement structure of a lane or a median. I have used this subassembly to create sidewalks, for example. It is always good to give it a chance.

Finally, if none of the previous satisfy your needs, you can create a custom subassembly using Subassembly Composer. 

Best regards!

[soonhui]

@ecfernandez , for this "To compute those quantities, you just need a Datum surface and an EG surface. Since you can add the Datum code to the Link Code field of this subassembly, Civil 3D will create the surface on the area covered by the link, enabling volume computation."

It's fascinating to learn this! You can a sample drawing/guide on how to do this?