Extend a surface

[rajeshpatnaik2001]

Hello,

I use Civil 3D 2011.
I have created a surface from a point group. Now i want to extend the surface to an outer boundary.
To do so, i do the following steps:

- Select the surface and Extract the border object.
-  Create feature line from the extracted border polyline
- offset this feature line (featureoffset) to outside psecifying a offset distance and  specifying the elevation difference as 0.
- Add this offseted new featureline as the boundary in the definition of the surface
- Rebuild the surface

Now when i am selecting the surface, I see that the featureline is not a part of the surface and I do not fint the contours and the TIN extending to this new boundary. Also I still find the old border in the surface.

I think I am doing something wrong in the process. Please let me know where I am wrong.

Thaks in advance

[neilyj666]

If the original border was defined as Outer then it will remain so? Try adding the new featureline as a breakline first or move it up the surface definition listing

[rajeshpatnaik2001]

Thanks Neilyj

I tried by adding the new featureline as a breakline. Now the surface extends to this new boundary and a new border object is created. But when I delete this breakline, the extended surface shrinks back to it's original shape. How to retain the extended shape of the surface after deleting the breakline?

Thanks.
 

[neilyj666 · Accepted solution]

In the Surface Propoerties > Definition > Build dialog, set the Copy deleted dependent objects to YES

[BrianHailey]

A couple questions:

1. Did you do any sort of surface edits around the edge of the surface such as delete lines?
2. Did you add an outer boundary to the surface (not to be confused with the border of the surface, the border simply displays the outer edge of the surface differently and this is what you are extracting)?
3. Can you give us a picture of the definition tab of the surface properties?
4. Can you share the drawing?

[troma]

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@rajeshpatnaik2001 wrote:

...

when I delete this breakline, the extended surface shrinks back to it's original shape. How to retain the extended shape of the surface after deleting the breakline?

 ...

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Why do you need to delete the breakline?  Can't you just leave it there?

I agree with Neil, you can use the 'copy deleted dependant objects' option.  But I'd really like to know why you are deleting it, and why you expect to be able  to delete it without the surface reverting back (without that setting).  

[rajeshpatnaik2001]

Thank you all!

Thanks Neil, by setting "Copy deleted dependent objects" to YES, solved my problem.

I am new to civil 3D and I am trying to do some volume calculations, grading design etc. with the help of this software. I am still learning this software.
Deletion of breakline was not needed. Just out of curiosity I wanted to know how to retain the surface shape after deletion of breakline.

Thanks.