Civil 3d Grading Problem

[kmedeiros1]

Hello, I am working on a project where I have to create pads on a property.  3 of the 4 pads came out just fine, but the fourth is creating contour lines on the pad that should be level.  The feature line of the pad is all a uniform elevation and I double checked each point to verify they are correct.  So why are the countour lines still in the pad? I attached an image of the pad.

I am using Civil 3d 2009

[troma]

Open the surface properties and look at the definition tab. What is listed in the bottom part of the box?

[kmedeiros1]

in the definition tab. The operation type box has nothing listed in it.

[troma]

The only one with nothing should be a data shortcut surface...as far as I know. Otherwise it should list everything used to create or edit the surface:
Add breakline
Add boundary
Raise/Lower etc.

Sure you clicked on the right surface?
Try close the program and recover the drawing...

[kmedeiros1]

I used the surface profile from the original surface and it was blank. This is what my surface of the pad says.

[troma]

Hmm...wonder what else is going on in that grading group. Did you create the surface as an infill grading? Something is giving extra data where you don't want it.

Simplest way I know to create a surface from a feature line is to click on the featureline, right click and select 'Add to surface as breakline'. Then you can click the plus sign and create a new surface. Follow through the options in the boxes, click OK a few times and hey presto! a new surface containing only that featureline and nothing else. Personally that's what I'd do and avoid gradings where possible.

[kmedeiros1]

Ok so I followed your steps now how do I create a grade from the breakline so I can find cut/fill quantities and see the contours?

[troma]

Not sure what "create a grade from the breakline" means. If you followed the steps you have already got a surface from that breakline. Do you mean a comparison between the pad and the existing ground surface?
Create a TIN Volume surface. Select your existing as the base, and this pad as the comparison surface.

[kmedeiros1]

sorry my vocabulary isn't the best when I try to be technical. I want the pad boxed by the blue line to have new contours like the other three pads boxed by the purple line.

I drew these shapes by polyline, then used elevation editor to bring all points of the pad to the same elevation.  then made the pad a feature line.  after that I went into grading and created a grading for each pad using my originial surface.

Thats what brought me to the original problem for the 4th pad (boxed by blue line). Wondering why it worked for the other pads and not that one, if all points were the same elevation.

So i tried the 4th pad your way and created a breakline, I can't create a grade from a breakline the way I did it originally so how do I get the new grade/contour lines?  Hope this makes sense.

[dgordon]

when a polyline with this shape is added to a surface, the contour lines connect the closest vertices together. yes, it is flat but that means that the contours can go from any vertice to any vertice. This is very confusing to the computer. put a point in the middle of the polygon that is 0.1' higher than the contour elevation. one or two other points like this may be required to clean up the contours. This is not a error in the way c3d calculates contours, its a symptom of how the information is being added to the surface.

[troma]

I often do similar flat horizontal surfaces, for example to get the volume of water in a pond.  But I don't expect to see any contours at all on a flat surface.

I'm not sure what contours you want to see.

Is is the new contours of the flat surface?  In which case: no contours is right.

Is it the contours of the existing surface within the box?  In which case: you're going about this an odd way.

Is it the cut/fill contours of a comparison between old and new?  In which case: see my last post.

I don't understand this part:

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@kmedeiros1 wrote:

I drew these shapes by polyline, then used elevation editor to bring all points of the pad to the same elevation.  then made the pad a feature line.  after that I went into grading and created a grading for each pad using my originial surface.

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What is the original surface for?  For what purpose is it included in the grading and what are you trying to acomplish with it?

Were all of the pads similar?  Are they all intended to be flat surfaces?  Because the ones in purple look weird to me; they have all sorts of contours going on.  There's some step in your process that I'm not understanding.

[Joe-Bouza]

post the file.

what is the green squiggle on the right side?