Contour lines across a curve and unable to add lines to the TIN

[cslatteryAXGRE]

Hello, 

I have a situation where there is a radius on some grading, a contour line will be placed on the curve, but one will also be placed as a chord across the curve. As shown. All of these points are at the same elevation. This does leave an empty space in the surface that I cannot fill by adding a line. To delete this line, I have to remove one of the blue lines, then I have a larger hole in the surface that cannot be filled. I also have another large area where there is a hole in the surface. No matter how I place the lines, the triangles do get created. I had these openings in other locations but they filled in easily. Does anyone have any ideas? Thanks

[ecfernandez]

Hi @cslatteryAXGRE, that might be happening due to previously erased triangles whose record is saved within the surface's definition.

If your surface is small, you can find what is the conflicting edit and delete it so you can create the triangulation as desired again. You can check the coordinates of each edit here:

Once you find it, right click it and delete it:

If you don't want to do that, you can alternatively follow this workaround:

1. Select your surface. Then, from the ribbon, select "Edit Surface." Then select, "Add Point."

If you are not using Civil 3D 2025, you might need to turn on points firstly here:

2. Add a point in the middle of your TIN line, as shown in the following image (yellow triangle). That should be enough to make Civil 3D create triangulation again on that empty area (as the pink lines show). However, if it does not create or does it incompletely, I encourage you to add a few more points in adjacent TIN lines until the hole is closed.

I hope this helps. Best regards!

[cslatteryAXGRE]

Thanks. I will try this. Yes I did delete some triangles trying to get rid of this line. It originally appeared on its own when I first created the surface  

[ecfernandez]

Hi @cslatteryAXGRE, Happy to help. Give it a try. I'll be looking forward to reading your comments!

Best regards!

[rl_jackson]

As a general rule always delete point vs. lines, first. This will help in reducing the holes that might show up. Breaklines can be a friend and a enemy never add a point that is a breakline. I don't use proximity breaks for this reason. I draw a survey figure (97%) or a featureline to define the break line to reduce errors in the surface thereby limiting holes. Also you don't need every single point that was shot, sometimes just the proximity of 2 points being close together will create issues. Shot for the tangible data, all surfaces are just approximations of reality, we are not building a rocket ship to mars.

[cslatteryAXGRE]

Adding the point worked. There were a lot of deleted lines in the edit list so I could not find the one I needed. So I used the add point on that contour line and it worked. Thanks

[cslatteryAXGRE]

Thanks for the information. Yeah, I deleted both some points and lines. I may have deleted too many lines. 

Thanks

[ecfernandez]

It is nice that worked! happy to help you find a solution to that @cslatteryAXGRE 

Best regards!