how to extract corridor boundary ?

[robert.248186]

the problem: how to use the daylight outer boundary of a corridor to "punch" a hole through existing TIN surface?

why do I want to do this? when making rendering and animations the existing grade TIN passes through the corridor surface. I have tried pasting corridor and existing grade TIN surfaces into the EDIT part of a new surface definition and it works okay...except the links are now coplanar with new surface definition, which makes the render look terrible. I have made a solution to this by targeting the corridor surface the underside of the all the pavements, soils, ect. This way I can still use code sets and links.

i feel that it would be less tricky and faster if i could just (somehow) enter the corridor boundary into the new surface definition. that way the hole would dynamically update every time the corridor was altered. and i wouldn't have to fuss with all these contrived topsoil and subsoil layers on non paved subassemblies.

[valejandro_ibarra]

in the corridor properties create a surface using top links, then switch to the boundary tab, and add the boundary using an automatic option or manually, then using surface utilities extract the border

hope it helps

[PGP-LA]

I'm experiencing exactly what Robert describes below. I tried the suggestion to extract corridor surface borders and re-use them as "hide" boundaries in the underlying surface and that does work, but isn't that a "static" solution? Those extracted borders are not dynamic, right, they're just 3D Polylines floating in space, un-linked to anything? I was trying to achieve what Robert described... ...cutting a "hole" in the underlying existing conditions surface that precisely outlines the corridor (and thereby improves rendering clarity because the corridor TIN lines are the only ones visible in the roadway... ...no pesky "existing conditions" TIN lines interfering) while ALSO maintaining a dynamic linkage for corridor edits.

Thank you both, by the way, for the question and the answer, which helped me move closer to what I wanted to achieve. It's nice to go "needle-in-a-haystack" hunting and actually find the needle.

Still curious about whether there is an answer that maintains the dynamic functionality that makes Civil 3D so powerful.