AutoCAD Civil 3D General Discussion

AutoCAD Civil 3D General Discussion

Reply
Active Member
ajmagnotta
Posts: 8
Registered: ‎03-10-2007
Message 1 of 6 (201 Views)

Civil 3d v2009 Surface Creation

201 Views, 5 Replies
05-04-2012 07:33 AM

I need to create a subgrade surface for a landfill project.  I have already created profiles and sections on a 200x200 ft grid along a baseline alignment that follows the center of the proposed landfill.  In my profiles and section views I have drafted in my proposed subgrade elevations.

 

Is there any way to create a surface by selecting critical points along the profiles & sections?  I would prefer not to use a grading group b/c the site is in excess of 200 Acres, and the grading tools tend to crash Civil 3D 2009 on large sites.

 

Thanks. 

*Expert Elite*
Sinc
Posts: 6,207
Registered: ‎11-18-2006
Message 2 of 6 (187 Views)

Re: Civil 3d v2009 Surface Creation

05-04-2012 12:10 PM in reply to: ajmagnotta

If you have Profiles and Sections (which I assume means you have a Corridor), can you create Cogo Points from the Corridor, then use those Cogo Points to create a subgrade surface...?  You may also be able to create the subgrade surface directly, as a Corridor Surface, using something like the "datum" code in your subassemblies.  It's difficult to indicate the best procedure to follow, without knowing more details about what you're doing and how.

 

And of course, if at all possible, it would be best to upgrade to C3D 2012.  That version is MUCH superior to C3D 2009.  And there have been enough problems with C3D 2013 that I'm not trusting it quite yet.

Sinc
Active Member
ajmagnotta
Posts: 8
Registered: ‎03-10-2007
Message 3 of 6 (166 Views)

Re: Civil 3d v2009 Surface Creation

05-06-2012 06:55 PM in reply to: Sinc

Unfortunately, I cannot use a corridor or grading group to create the surface for this project.  Currently, the profiles & sections were created from EG & FG TINs developed from Aerial Survey and polyline grading, respectfully.  To complete the project, I need to add benches, swales, basins, etc.

 

Typically I would try to create this via a corridor model, but in this instance I will need to provide initial, final, and subgrades (bottom of liner) for a project that will occur over 3 phases, where the grading overlaps between phases.

 

That being said, rather than creating a multitude of corridors, I would like to build my surface off of points taken along my profiles & sectons where I can easily create polylines to represent my final grading. 

 

Note that I created my 200'x200' grid using 2 perpendicular alignments (each 3,000' long) w/ sample lines at 200' intervals.  If I was able to create the above noted points along my sections, then I believe that Civil 3D could assign corrdinates based off of the station & offset of section view, and derive the elevation of each point as well.  I am just not sure on how to go about doing that (or know of an easier alternative).

 

Thanks for your time & assistance in this matter.

 

*Expert Elite*
BrianHailey
Posts: 2,819
Registered: ‎04-27-2005
Message 4 of 6 (160 Views)

Re: Civil 3d v2009 Surface Creation

05-06-2012 08:54 PM in reply to: ajmagnotta

If you are just trying to draw something in your section and then use it as data in a surface, create a corridor (I know, you said you didn't want to create one, just keep reading). It doesn't really matter what's in the corridor, just create one along the alignment. Now go into your section editor and add the data you want. The section editor actually takes your drawing, flips it so you are looking at the section, aligns your UCS with it, and then clips the drawing either side of the section. In other words, you are now drawing in the section, not a representation of the section. You can then draw whatever you need, 3d polylines, points (I'm pretty sure you could put points there, though I've never tried), and just about anything else you want. Then take that data and add it to a surface.

 

Hope this helps.

Brian Hailey
CAD-1.com
My Blog
*Expert Elite*
Sinc
Posts: 6,207
Registered: ‎11-18-2006
Message 5 of 6 (156 Views)

Re: Civil 3d v2009 Surface Creation

05-07-2012 12:06 AM in reply to: ajmagnotta

ajmagnotta wrote:

Unfortunately, I cannot use a corridor or grading group to create the surface for this project.  Currently, the profiles & sections were created from EG & FG TINs developed from Aerial Survey and polyline grading, respectfully.  To complete the project, I need to add benches, swales, basins, etc.


 FG TINs from an aerial survey...?  That confuses me.


ajmagnotta wrote:

 

Typically I would try to create this via a corridor model, but in this instance I will need to provide initial, final, and subgrades (bottom of liner) for a project that will occur over 3 phases, where the grading overlaps between phases.


This makes more sense to me, and ties in with my years-old "Project Rant".  C3D has no concept of a "Project", which makes it difficult to manage "Project Phases".  I wish Autodesk would address this problem.  Unfortunately, they seem to have confused "Project Management" with "Model Data Management" and "Document Management", and left "Project Management" as non-existent.


ajmagnotta wrote:

That being said, rather than creating a multitude of corridors, I would like to build my surface off of points taken along my profiles & sectons where I can easily create polylines to represent my final grading. 

 

Note that I created my 200'x200' grid using 2 perpendicular alignments (each 3,000' long) w/ sample lines at 200' intervals.  If I was able to create the above noted points along my sections, then I believe that Civil 3D could assign corrdinates based off of the station & offset of section view, and derive the elevation of each point as well.  I am just not sure on how to go about doing that (or know of an easier alternative).

 

Thanks for your time & assistance in this matter.

 


 You kind of lost me there...  Not sure what you're trying to do with this approach, or why you're taking it.  I suspect that we"re thinking of different things when we use the term "sections"....  I tend to think of "sections" as something created from a C3D Corridor...  I'm guessing you have a different view...?

Sinc
Active Member
ajmagnotta
Posts: 8
Registered: ‎03-10-2007
Message 6 of 6 (149 Views)

Re: Civil 3d v2009 Surface Creation

05-07-2012 06:48 AM in reply to: ajmagnotta

First of all, thanks for the feedback.

 

Based on the responses, I am going to try a corridor model for this project.  However, the method that I am attempting is how our office created the grading for our other 2 landfill projects (done in R14/Softdesk & later LDT).  In this methodology, offsets along a section were assigned a respective coodinate value along the baseline, elevations were recorded & a PNEZD point file was created by hand.  Which thank god I wasn't here to plug in all those points by hand! 

 

As is typical w/ Civil 3D management is still resistant to fully commit to Corridor Modelling in Civil 3d.  I am slowly wearing them down, but that is a discussion for another day.

 

Anyway, to answer some questions.  By Sections, I am referring to Sample Lines created from an Alignment (similar to LDT).  Sorry, the EG was created from Aerial Survey, & the FG was created from polylines.  I currently have no corridor models or subassemblies for this project.  All of my profiles & sections have been created from surfaces (not by layout).

 

If I can create the corridor model, I think that should most-likely negate the need for the points, but if I can add points through the section editor in the corridor model, then why can I not do the same in my profiles & sections generated from the surfaces?

 

I have attached a sketch of the methodology that I am attempting to use for this project. 

 

Thanks again.

Post to the Community

Have questions about Autodesk products? Ask the community.

New Post
Need installation help?

Start with some of our most frequented solutions or visit the Installation and Licensing Forum to get help installing your software.