contours within closed corridor "loops"

[carl809630]

I have a large corridor that loops around and closes on itself. It seems to want to "auto fill" the contours in the center and snapping to corridor extents only effects the outside of the loop....

I can delete by hand but I want to be able to past existing surface and corridor surface data into a new surface to show the finished design. However, every time I do that the deleted contours re-establishes over the existing...I just want new contours where the corridor is!!

Any ideas here?

[mjfarrell]

Carl, what is happening is that the feature line and point codes at the inside edge of your corridor are being connected; as that is the nature of a TIN.
You will need to apply a Surface boundary (Inside) to that surface and then you can (or should) make two(2) copies of your Existing surface, and edit away all data on the inside being replaced by the new corridor surface extents with one. And edit away all data outside the middle of that doughnut hole made be the closed loop of the corridor and paste the outside and inside surface(s) into the bounded corridor surface for best results.