AutoCAD Civil 3D General Discussion

AutoCAD Civil 3D General Discussion

Reply
Active Contributor
yasin2ray
Posts: 27
Registered: ‎02-22-2011
Message 1 of 12 (1,519 Views)
Accepted Solution

Contain Cut/Fill to a portion of the site - How to?

1519 Views, 11 Replies
12-20-2011 12:30 PM

I would like the grading of a site to happen only on part of the site; I need the rest of the site to remain unchanged.

 

I thought I was finished with this project, the volumes seemed about correct, and then I noticed in the comparison surface (showing areas of Cut and areas of Fill) that soil is being taken from parts of the site that need to remain undisturbed. This is a residential site with a conservation easement and other forested areas that we won't be disturbing.


How do I set a boundary or breakline (or what?) to limit the grading/cut/fill to the area I want?

 

Thank you!

Anna

AutoCAD Civil 3D 2010

yasin2ray wrote:

I took a guess and tried making the magenta line into a "Non-destructive Outer Boundary" (which is what my property line currently is) but I got this error:

"Illegal (self-intersecting or non-closed) boundary polygon."

 

Am I on the right track?


Yes you are on the right track. You need to create a closed polyline from scratch, the error you are receiving tells you what is wrong with your current magenta boundary. I've had the same error before too! Usually the polyline isn't closed or has double vertices.

 

For the future, you might consider creating your proposed surface only to the daylight line. Create your closed polyline at the daylight line, and use it as the outer boundary for both the proposed and comparison cut/fill volume surface. If you need to show both propsed and existing as a single surface, you can clip the existing at the boundary line with the proposed surface shown. I think some here were confused that your proposed surface includes what looks to me like existing ground data.

 

~ Mary

*Expert Elite*
Joe-Bouza
Posts: 4,967
Registered: ‎12-15-2008
Message 2 of 12 (1,501 Views)

Re: Contain Cut/Fill to a portion of the site - How to?

12-20-2011 02:52 PM in reply to: yasin2ray

I don't full understand what you are saying but the limit of you fg grading is the limit of cut & fill unless you create a specific boundary to include only the area you want.

 

I read your post again and maybe what you want is to have a net 0 balance in your fg surface? If that is the case and you did the whole magilla with a GO - there are tools there to balance. Other wise it will mean trial and error by adjusting FG to get the number you require.

 

 

Thank you

Joseph D. Bouza, P.E. (one of 'THOSE' People) Civil 3D 2012 & 2013
HP Z210 Workstation
Intel Xeon CPU E31240 @ 3.30 Hz
12 GB Ram


Note: Its all Resistentialism, so keep calm and carry on

64 Bit Win7 OS
Active Contributor
yasin2ray
Posts: 27
Registered: ‎02-22-2011
Message 3 of 12 (1,496 Views)

Re: Contain Cut/Fill to a portion of the site - How to?

12-20-2011 03:44 PM in reply to: Joe-Bouza

Joe,

"unless you create a specific boundary to include only the area you want." That's exactly it! I want to know how to create a boundary to include only the area I want to have graded. The rest of the site needs to remain untouched.

 

I've attached a jpg showing my existing and proposed surfaces and the "volume surface" that shows Cut and Fill areas. There is a magenta line over each surface. I do not want the cut/fill to happen outside of the magenta line. I want the computer to do the grade changes inside the magenta line. (The cut/fill does not need to balance to zero; we expect to have to bring in soil from off-site).

 

The entire surface is bounded by the property line. I'm not changing the entire property, I'm only changing the grade inside of the magenta line.

 

I took a guess and tried making the magenta line into a "Non-destructive Outer Boundary" (which is what my property line currently is) but I got this error:

"Illegal (self-intersecting or non-closed) boundary polygon."

 

Am I on the right track?

 

Anna

 

AutoCAD Civil 3D 2010
*Expert Elite*
mathewk
Posts: 2,753
Registered: ‎07-09-2003
Message 4 of 12 (1,476 Views)

Re: Contain Cut/Fill to a portion of the site - How to?

12-20-2011 06:50 PM in reply to: yasin2ray
Part of your proposed surface lies outside of that magenta polyline. I don't understand how you don't want to calculate volumes for this area if it is above or below the exisrting ground.
Matt Kolberg
Cansel - Autodesk Division
http://www.cansel.ca/
*Expert Elite*
neilyj
Posts: 3,790
Registered: ‎08-01-2008
Message 5 of 12 (1,461 Views)

Re: Contain Cut/Fill to a portion of the site - How to?

12-21-2011 01:55 AM in reply to: yasin2ray

So what you want is for the magenta line to be the top of the cut slope and bottom of the fill slope - so this could mean having variable slopes in the cut and fill to remain in the magenta envelope??

 

You could try an alignment and corridor with a width / elevation target (although I have'n't thought how this would work in practice)

 

OR

 

create a feature line from the magenta line and drape over the EGL then grade inside to the proposed levels using grading objects or offset feature lines

neilyj
(No connection with Autodesk other than using the products in the real world)


IDSP Premium 2015 (mainly Civil 3D 2015 UKIE & Infraworks with some limited 3ds Max Design)
Win 7 Pro x64, 240Gb SSD, 1Tb HDD
32Gb Ram Intel Xeon CPU E5-2650 v2 @ 2.6GHz (32 CPUs), ~2.6GHz
NVIDIA Quadro K4000, Dual 27" Monitor, Dell T5610
Active Contributor
yasin2ray
Posts: 27
Registered: ‎02-22-2011
Message 6 of 12 (1,438 Views)

Re: Contain Cut/Fill to a portion of the site - How to?

12-21-2011 08:14 AM in reply to: mathewk

Yes, the property exists inside and outside of the magenta line. A house has been put in the middle of the property and the grade is changing only near the house. Outside of the magenta line grade is not changing.

 

To address mathewk's sentence, I don't want to calculate volumes for that area because.... existing ground is NOT changing there. There is to be no change. All the spot elevations outside the magenta line are staying exactly the same. Inside the magenta line, they are changing.

 

The Proposed surface is correct, but it's the Cut/Fill surface that is moving soil around outside of the magenta line. I cannot show that to the homeowner because he'll think we're planning to move soil there, and we're not.

 

I do believe this is a very simple problem. This is probably a task people perform all the time - you have a site where grading is changing on part of it and staying the same on another part.  I'm new to Civil 3D so this can't possibly be an advanced question. You all seem very experienced, and I apologize if this does not have an exciting resolution!

 

One thought I had was that I might need to create a new Outer Boundary that hides the area that is not changing. That way, it would be left out of grade calculations. The problem with that is, I believe, to compare two surfaces they need to be the same size/dimensions. Right?

 

Or perhaps I need to make a breakline out of the magenta line so that grading will not happen across the magenta line. ???

 

Please keep trying to help me. I really need to figure this out and I haven't found any help in the User Guide or YouTube tutorials.

 

Thank you,

Anna

AutoCAD Civil 3D 2010
Valued Contributor
gknobbe
Posts: 69
Registered: ‎10-13-2006
Message 7 of 12 (1,427 Views)

Re: Contain Cut/Fill to a portion of the site - How to?

12-21-2011 09:26 AM in reply to: yasin2ray

You are correct that you can create a boundary and hide the surface, this will exclude the area that you do not want to have in your volume calc. The calculation is only going to be made on what is there. You will notice that when you hover over the area that you have created the hide boundary that there is no surface elevation.

 

The two surfaces that you are running the volume calcs on do not need to be the same size.

*Expert Elite*
MarySeufert
Posts: 581
Registered: ‎04-19-2011
Message 8 of 12 (1,416 Views)

Re: Contain Cut/Fill to a portion of the site - How to?

12-21-2011 10:23 AM in reply to: yasin2ray

yasin2ray wrote:

I took a guess and tried making the magenta line into a "Non-destructive Outer Boundary" (which is what my property line currently is) but I got this error:

"Illegal (self-intersecting or non-closed) boundary polygon."

 

Am I on the right track?


Yes you are on the right track. You need to create a closed polyline from scratch, the error you are receiving tells you what is wrong with your current magenta boundary. I've had the same error before too! Usually the polyline isn't closed or has double vertices.

 

For the future, you might consider creating your proposed surface only to the daylight line. Create your closed polyline at the daylight line, and use it as the outer boundary for both the proposed and comparison cut/fill volume surface. If you need to show both propsed and existing as a single surface, you can clip the existing at the boundary line with the proposed surface shown. I think some here were confused that your proposed surface includes what looks to me like existing ground data.

 

~ Mary


_______________________________________________________________________
Normal people believe that if it ain't broke, don't fix it.
Software Engineers believe that if it ain't broke, it doesn't have enough features yet.
Active Contributor
yasin2ray
Posts: 27
Registered: ‎02-22-2011
Message 9 of 12 (1,390 Views)

Re: Contain Cut/Fill to a portion of the site - How to?

12-21-2011 05:43 PM in reply to: MarySeufert

MarySeufert,

I recreated the magenta boundary which had been giving me the error message. It was a closed polygon already so I wasn't sure what the problem was. The Outer Boundary was successful and the Proposed surface has been clipped to show only the 'area where grading is occurring'.

 

I rebuilt all my surfaces, and now my Cut/Fill surface is the same size as the Proposed surface. That makes sense.

 

When I first created the Proposed surface, I didn't know the extent of the grading we'd be doing. Now I know to clip the surface as soon as I know the extent of grading, and 'unchanged' grade stays with the Existing surface.

 

I ran the new cut/fill number by my boss and he said that sounds right. Finally. Finally!

 

You can see (if you'd like) in the attached jpg, the proposed surface bounded by the magenta line, with the existing surface behind it. All the elevations run into each other, so it looks like its working. and the final cut/fill surface takes nothing from the area that will remain ontouched.

 

Thank you everyone! I'm a little hesitant to say it, but I think the problem is resolved.

 

One more lesson learned.

Anna

 


AutoCAD Civil 3D 2010
Active Contributor
yasin2ray
Posts: 27
Registered: ‎02-22-2011
Message 10 of 12 (1,386 Views)

Re: Contain Cut/Fill to a portion of the site - How to?

12-21-2011 05:47 PM in reply to: MarySeufert

I might also add to your point:

 

"I think some here were confused that your proposed surface includes what looks to me like existing ground data." 

 

I didn't know they had to be separate! I had figured, if, say, as location with elevation 765.5 is remaining 765.5, it's okay to show it on both exisiting and proposed surfaces... because 765.5 is part of what I'm proposing for the site.

 

I'll keep them separate from now on.

 

AutoCAD Civil 3D 2010
Announcements
Are you familiar with the Autodesk Expert Elites? The Expert Elite program is made up of customers that help other customers by sharing knowledge and exemplifying an engaging style of collaboration. To learn more, please visit our Expert Elite website.
Need installation help?

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