AutoCAD Civil 3D General Discussion

AutoCAD Civil 3D General Discussion

Posts: 14
Registered: ‎12-11-2012
Message 1 of 5 (562 Views)
Accepted Solution

Merging corridor surfaces that run parallel to each other

562 Views, 4 Replies
12-11-2012 02:59 PM

How do I merge 2 corridor surfaces that are running parallel to each other. Due to this being an overlay project the CL will stay the same just raised 4.5" from existing CL and the existing cross slope varies which we are matching until you hit the sawcut. We are not ripping out or milling any apshalt, it is strictly an overlay of the exisitng with 4.5" of new asphalt. We are saw cutting 2' either side of theedge of paveement and matching in with proposed.  


 I have created a feature line over the existing cl then raised it the required height. the cl has been offset 10 both sides to create my left and right shoulder alignments,  I then created a left and right shoulder corridor assembly which has supplied 2 seperate surfaces. I now would like to merge the 2 surfaces using the raised cl feature line as a break line to create the final proposed surface. I would prefer not to have to create feature lines from my corridor and create a new surface because i would like to take asphalt and subgrade quantaties at the end with out having to hand calc but will if need be.


any help or ideas would be much appreciated.

Valued Mentor
Posts: 1,094
Registered: ‎01-07-2011
Message 2 of 5 (556 Views)

Re: Merging corridor surfaces that run parallel to each other

12-11-2012 04:10 PM in reply to: E_Shaft

It would be really helpful if you posted a picture, however it sounds like you can do this with one Corridor and one Corridor surface.


Two Offset Assemblies at your sawcuts and Links up to your CL crown (crown sampled from EG and raised 4.5")



Fred Ernst, PE
C3D 2015
Ernst Engineering
*Expert Elite*
Posts: 2,105
Registered: ‎11-08-2005
Message 3 of 5 (550 Views)

Re: Merging corridor surfaces that run parallel to each other

12-11-2012 04:41 PM in reply to: E_Shaft

Take a look at the help files for the OverlayWiden subassemblies.  Based on your description it sounds like they will do exactly what you want.

Valued Contributor
Posts: 92
Registered: ‎02-01-2007
Message 4 of 5 (536 Views)

Re: Merging corridor surfaces that run parallel to each other

12-11-2012 08:49 PM in reply to: sboon

An image would be helpful so we can better understand what you are tring to achieve. Sounds to me that you are just tieing down to an existing corridor surface but with a different shoulder height and location. Can you not just create a volume surface based off the 2 road surface? Then maybe run cross sections to see volume cut/fill per every 50'. It's my understanding that the existing corridor is acting as you existing surface. 




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Civil 3D 2012/2013

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Posts: 2,520
Registered: ‎05-21-2008
Message 5 of 5 (515 Views)

Re: Merging corridor surfaces that run parallel to each other

12-12-2012 07:36 AM in reply to: tony1978

If you have done too much work to go back and start with a different approach, and this is simply a question of merging surfaces, you can paste them together.  Make a new surface and then paste in the two you have, to make one large surface.  You can also add other data afterwards (such as an additional feature line).

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