topic Re: Offset a 3d polyline/feature line with specific slope and grading in Civil 3D Forum

Offset a 3d polyline/feature line with specific slope and grading

dorvoscristian20 — Wed, 14 Apr 2021 07:50:16 GMT

Hello,

It's been a while since I've been trying to find out how I can offset a 3d polyline/ feature line with a final grading percent and slope between also.

I tried here a sketch with the situation.

Thank you!

Re: Offset a 3d polyline/feature line with specific slope and grading

Anonymous — Wed, 14 Apr 2021 10:53:38 GMT

You can use grading tools on feature lines and 3d polylines. If you edit the grading criteria you set the target (distance, elevation, relative elevation, surface) and projection (slope, grade) .

Re: Offset a 3d polyline/feature line with specific slope and grading

dorvoscristian20 — Wed, 14 Apr 2021 11:10:35 GMT

I was trying, what I can set is the slope or grade between the 2 feature lines, what I need is the slope (2.00:1 example) and the final grading elevation to have ( 2% slope), that for me means that I can not set a target like distance or elevation or surface, because non of this are fixed. (sorry for my English, I m trying my best) 🙂

Re: Offset a 3d polyline/feature line with specific slope and grading

Anonymous — Wed, 14 Apr 2021 11:37:54 GMT

two feature lines that both have elevations means there is a predetermined slope between them. But you want a 2% slope. Should the grading at 2% end where the second feature line is? It sounds to me like you need to create a fake surface that is almost, but not quite, vertical at the "target" feature line. So that the grading will go out at 2% until it hits the "vertical" surface at the second feature line. The result will be a third feature line on top of or below the second feature line that is 2% slope away from the first.

Or, just do it manually. Draw lines between the two feature lines, adjust the Z at the end at the second feature line to be 2% from the first feature line, then draw a new feature line snapping to the ends of the lines drawn.

Of course, I probably totally missed what you are trying to do here.

Re: Offset a 3d polyline/feature line with specific slope and grading

dorvoscristian20 — Wed, 14 Apr 2021 11:39:24 GMT

I will attach a small drawing and I hope that will explain better what I m trying.

-the green road is an existing one

-the red one is what needs to be build ( I god this result by doing it manually, vertex by vertex) - Is there anything more easy that I can do?

Re: Offset a 3d polyline/feature line with specific slope and grading

Joe-Bouza — Wed, 14 Apr 2021 12:00:32 GMT

"elevation by adjacent grade does this"

Re: Offset a 3d polyline/feature line with specific slope and grading

Anonymous — Wed, 14 Apr 2021 12:52:50 GMT

I am still not sure what you goal is, but see attached. at the "target" 3d polyline, I created an almost vertical surface by offsetting the 3dpoly a very small distance and up/down 25m. Then I created a grading object with the feature line at 2:1 slope into the vertical surface. Is this what you are trying to accomplish?

Re: Offset a 3d polyline/feature line with specific slope and grading

dorvoscristian20 — Thu, 15 Apr 2021 05:04:58 GMT

Good morning,

Thank you for all your answers, not really, what I want to accomplish is exactly what I have attached ( the green road is existing one, and I m looking for a tool that can build the red berm more easy than I m doing it now, now i make a feature line and from the level of the existing road using the elevation table I m giving the 3% grading and after I will just move each vertex closer of further than the existing road to reach the 2.00:1 slope.

Thank you

Re: Offset a 3d polyline/feature line with specific slope and grading

dorvoscristian20 — Thu, 15 Apr 2021 05:55:04 GMT

Thank you for your answer, but I think that this tool is fixing half of my problem, will fix the slope/grading between the 2 feature lines by chancing the levels of the targeted feature line but will not give me the 3% slope on the targeted feature line, because for this the tool needs to change the position of it not only the level.

I think that the answer for my question can be find somewhere in the grading tool, but I just don't find out where and how to ask for it 😞

Thank you again

Re: Offset a 3d polyline/feature line with specific slope and grading

Anonymous — Thu, 15 Apr 2021 10:46:00 GMT

Attachment?

I am starting to wonder if a corridor is what you want as we now seem to have two slopes, 2:1 & 3.0%.

Re: Offset a 3d polyline/feature line with specific slope and grading

Joe-Bouza — Thu, 15 Apr 2021 18:51:45 GMT

I had that same thought. However, if the new road is to have a constant grade the position of the new road would vary depending on the profile grade desired and the cross slope of the embankment.

the new road meets the existing at a point. if that point were held and the constant grade drawn back in profile . then an assembly set on the existing road FL with a link slope elevation target should place the new road.

Re: Offset a 3d polyline/feature line with specific slope and grading

Joe-Bouza — Thu, 15 Apr 2021 22:53:17 GMT

@Anonymous & @dorvoscristian20 works like a charm

of course it can be refined once determined

Re: Offset a 3d polyline/feature line with specific slope and grading

dorvoscristian20 — Sun, 18 Apr 2021 05:05:17 GMT

This looks like a solution for my issue. I will try it to see how works.

Thank you!