CAD Survey Spot Elevations - How to add to a surface?

[rdavisMX6RG]

Hi,

I am trying to learn civil 3d as I go so apologies for any silly questions.....

I have a CAD .dwg of a survey of a field.  The field is very flat so there are very few contour lines shown.  The surveyor has naturally given me spot elevations in between the contours to tell me the local levels.  I can make a basic TIN surface from the contours by "Create Surface" => Definition=> and add contours.  Draw a PLine for boundary and add this and I have my basic surface.

For me to add the Spot Elevations though, to give the surface more definition, how do I do this?  The spot elevation text have Z values, as does the node beside it.

Any help very welcome.

[rl_jackson]

When you say you're creating a surface from contours, was that something that was already available. Is the data reliable? If you have data from the surveyor, you should use that to create a TIN surface either by creating a group for you surface points and adding that to you EG (existing ground) surface. As for spot grades, if you have enough information from the surveyor to create a surface once complete you could use spot elevation labels or spot elevation labels on a grid to interpolate you TIN model and provide a elevation, or if you so choose to use the data that the surveyor provided and just style it however you wanted it to look.

[AllenJessup]

CAn you post the drawing or at least a portion with some spot labels in it. There may be a couple of options. But that depends on how the spot labels were created.

[rdavisMX6RG]

Allen Jessup,

.dwg attached.  Basically I'm trying to form surface, very few contours so need to use the spots (Layer existing surface).

Probably very straight forward but I am new to the civil 3D.

Thanks for assistance.

[cwr-pae]

Xref the file with the surface and use the cogo points as spot elevations. Control the display/filtering with point groups. Which is what we typically do for existing grades.

Or dref the surface and import selected cogo points as spot elevation (again using point groups).

Or dref the surface and create spot elevations on a grid plus add any you think are necessary at critical spots (on curbs, gutters, etc.). What we typically do for finished/design surfaces.

Or Dref the surface and create cogo points on a grid and along lines (such as curb lines pavement edges), select the point group and set the elevations to the dref'd surface.

Or a combination of any of the above.

My vote would be the first option but there many ways to accomplish your goal.

[AllenJessup · Accepted solution]

Looks like you got an easy one. The blocks that show the "X" are at elevations. Add them to the Surface.

[rdavisMX6RG]

Sorry,

just back on this again now.

When I select the marker blocks and add to the surface, should the triangulation in the surface not change to show me that the CAD elevation marker is now part of the surface??  Or am I totally off the mark?

[AllenJessup · Accepted solution]

If the Surface isn't set to Rebuild Automatic. You might have do a Rebuild.

[rdavisMX6RG]

Hi again,

Im back on this one again. (Work so busy not getting much time to learn/practice the excellent advice given here)

This one is frustrating the heck outta me. 

We get surveys in CAD format, with the contours shown and spots usually in block format.

I create the surface using the "..definition=>Contours" tab and all contours form my surface.  That part is ok. 

But, especially on flat sites, there may be very few contours so the surveys are made up of spots.  I have gone through the above steps to add the spots but, as per attached image, my surface triangulation is not hitting the points?

Bar manually going around and forming points in my dwg, how can I just add these to form part of my triangulated surface?

Tbh I'm not sure I'm even explaining my issue correctly.

(I'm still a newbie so if any reply can be made as simple as possible, I would be very grateful)

 

[Pointdump]

Hi Ray,
Best practice for creating surfaces is to add your best data first. And if you want TIN lines hitting your Block spots, draw 3D Polylines or Feature Lines through them and then add those first to your Surface as Breaklines.
Dave

[rdavisMX6RG]

Hi again,

I think I solved my problem, by accident tbh.

I made a surface from only my contours (EG Contours)

Then, I had to make a another surface (Topo Blocks)

I highlighted the relevant spot elevation blocks and "select all" and then isolate.

Even though they already had an elevation, under "Modify">"Surface">"Move to surface" I had to move the blocks to the attribute elevation.

When this was done it was a simple exercise of adding these new blocks under Definition>Drawing Objects>Add>Blocks to that surface.

Finally, I made a Master "EG Topo" surface and merged the 2 surfaces into this.

The above worked for me on this.  There may be a more simple method but it gets me over the line for today 🙂

As always, thanks for the responses above.