Roundabouts with One Way Roads

[BrianHailey]

So, if I try to model a roundabout at a highway interchange, the on and off ramps are one way. If I set the number of lanes forward (or backwards depending on the direction drawn), why does my roundabout still have two way flow? Is there any way to adjust this?

[BrianHailey]

The traffic simulation seems to handle it ok though...

[nigel_peters · Accepted solution]

Brian,

At the moment only two way approches are supported for roundabouts, there are changes in geometry to handle one way roads / grade seperated roundabouts, which the current generation code does not handle. We chose to way you show them in your image so it was clear they were not handled.

How important is this work flow for you.

Nigel Peters

Autodesk

[BrianHailey]

Hi Nigel,

Thanks for the response. How important is it for me? I work for a reseller so if someone asks if it can be done, it's critically important, if no one asks if it can be done, it's not important at all.

[Anonymous]

@Anonymous I work for a engineering consultancy where road design is a primary business. It is critical that roundabout tools be improved in upcoming releases. 

[Anonymous]

Are there any progress in this matter? Being able to design roundabout with one way arms is indeed essential and as I have been using InfraWorks extensively for many years now I am a bit surprised that nothing have been done to fix this.

[BrianHailey]

I haven't seen any improvement on this although it has only been four years since I asked this question. I haven't seen any improvement on the ability to draw two roads parallel with each other either. InfraWorks is pretty fancy but doesn't seem to work well for actual engineers unless they do very specific work that doesn't deviate from the way Autodesk thinks things should be designed.

[Anonymous]

yup. Still waiting for basic improvements that would seem to be simple such as creating diverge and merge tapers at exit and entry ramps that are to road authority standards. It would seem beneficial that autodesk employ a road designer to actually be a part of the development of the software. I’ll put my hand up and do it for free just to get it sorted 🤣🤣. 

[Anonymous]

This is now the biggest issue we have with Infraworks and is preventing us from adopting it for actual road design.

As others have pointed out, without the ability to have single lane entry and exit at roundabouts, we can't get accurate volumes or quantities and our concepts don't reflect the real world.

Has anyone found any work arounds for this problem?? I tried to drawin in a roundabout manually but that just created an intersection at each road entry/exit 😕

[BrianHailey]

@Anonymous come on now. It's only been four and a half years since I originally posted this. You don't think Autodesk can actually get something done in InfraWorks that engineers need in that time frame, do you?

And, I'm still waiting to be able to draw two roads parallel to each other...

[jarsson]

2023 - "And, I'm still waiting to be able to draw two roads parallel to each other... or ...being able to design roundabout with one way arms" 😔

[foxnant07]

Sorry for resurrecting the topic. I want to create a 6-arm junction like the one in the picture in infraworks or civil 3D, but I couldn't do it. How can I create it?