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Grading transition

14 REPLIES 14
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Message 1 of 15
SMiddick
4122 Views, 14 Replies

Grading transition

I have a pond in the south west corner of my site. The top elevation varies from 1030 to 1029 and the bottom is 1027 on the west end. As you go towards the east end of the pond the side slopes stay at a 3:1 but the bottom of the pond slopes at a 200:1. I have added grading objects where I needed them to hit the different elevations and I am now trying to add a transition between the grading objects. I can not get this to work at all! I don't know what I could possible be doing wrong? I have not changed the target surface or the grading group or the grading type. When I pick between the two grading objects to create the transition Civl 3D acts like it has created the transition but my surface never changes and I don't see a new transition grading object.

 

ANY help is greatly appreciated!

14 REPLIES 14
Message 2 of 15
Neilw_05
in reply to: SMiddick

Civil 3D doesn't seem to support the transitions between the gradings you have set up. Even though your gradings are set to elevation targets, it reports that it can't transition between gradings with different surface targets.

 

I think you'll find a different workflow will give better results anyway. What I recommend is to create what I call a construction surface. What you would do is create a planar surface that represents the 200:1 sloped pond bottom.and use it as a target for the gradings for the interior sides of the pond. That way you won't need any transitions and you'll have a nice smooth pond. Once you have the sides graded just add an infill to complete the pond bottom.

 

To create the construction surface, just draw a rectangle that is large enough ensure the gradings will find a target and apply the elevations and slopes to tilt it according to your pond bottom requirements, then add it to the construction surface.

Neil Wilson (a.k.a. neilw)
AEC Collection/C3D 2024, LDT 2004, Power Civil v8i SS1
WIN 10 64 PRO

http://www.sec-landmgt.com
Message 3 of 15
SMiddick
in reply to: Neilw_05

I really like that idea! I'm going to try that a little later in the day. I guess I don't know when to use the transitions then? How do they work?

Thanks,
Stephen
Message 4 of 15
Neilw_05
in reply to: SMiddick

I don't know why your transitions don't work. If they did they'd look like you would expect. Try these scenarios to see how they should work:

 

Create a grading to a distance target at some slope, then create another with a different distance and slope with a gap between the gradings. Then apply a transition and you should see a warped grading between them. Officially you should be able to do this with any combinations of gradings except for gradings that target different surfaces.

Neil Wilson (a.k.a. neilw)
AEC Collection/C3D 2024, LDT 2004, Power Civil v8i SS1
WIN 10 64 PRO

http://www.sec-landmgt.com
Message 5 of 15
neilyj666
in reply to: SMiddick

There is a dll that Jeff_M wrote that will create a working plane from 2 or 3 picked locations and it will extend it too....search for Working plane in the C3D customization forum

neilyj (No connection with Autodesk other than using the products in the real world)
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AEC Collection 2024 UKIE (mainly Civil 3D UKIE and IW)
Win 11 Pro x64, 1Tb Primary SSD, 1Tb Secondary SSD
64Gb RAM Intel(R) Xeon(R) W-11855M CPU @ 3.2GHz
NVIDIA RTX A5000 16Gb, Dual 27" Monitor, Dell Inspiron 7760
Message 6 of 15
Neilw_05
in reply to: neilyj666

ll that's needed is a single featureline down the middle at the appropriate elevations and slope. Then apply gradings on both sides outward at 0% using a suitable distance target and make a surface from them.

Neil Wilson (a.k.a. neilw)
AEC Collection/C3D 2024, LDT 2004, Power Civil v8i SS1
WIN 10 64 PRO

http://www.sec-landmgt.com
Message 7 of 15
MikeEvansUK
in reply to: SMiddick

If Neil's suggestion doesn't work then another option is to create the main geometry and fill in the gaps, explode and join to create a single line.

Now use a corridor instead with a daylight to right of way and target the new featureline. The slopes will then transition from one to another perfectly.
Have used this trick a few times myself just watch the spacing or maybe work uphill instead.
Mike Evans

Civil3D 2022 English
Windows 7 Professional 64-bit
Intel(R) Core(TM) i7-3820 CPU @ 3.60GHz (8 CPUs), ~4.0GHz With 32768MB RAM, AMD FirePro V4900, Dedicated Memory: 984 MB, Shared Memory: 814 MB

Message 8 of 15
fcernst
in reply to: SMiddick

This is a Corridor daylighting down to a 200:1 pond bottom surface from your Top feature line:

 

 

Capture.JPG



Fred Ernst, PE
C3D 2024
Ernst Engineering
www.ernstengineering.com
Message 9 of 15
Joe-Bouza
in reply to: SMiddick

Haven't followed the whole thred but is it possible you are trying between two different criterior, i.e. grading 1 goes to surface and grading 2 goes to elevation?

Thank you

Joseph D. Bouza, P.E. (one of 'THOSE' People)

HP Z210 Workstation
Intel Xeon CPU E31240 @ 3.30 Hz
12 GB Ram


Note: Its all Resistentialism, so keep calm and carry on

64 Bit Win10 OS
Message 10 of 15
SMiddick
in reply to: Joe-Bouza

Thanks for all the input, everyone! I have built the pond with grading objects around the top and targeted a construction surface like Neilw suggested. This worked great. The only problem is when I want to chage the pond bottom to lower it 1' Civil 3D crashes every time. I was just trying to use the Raise/Lower surface edit. Maybe I need to use the Raise/Lower feature line that is defining that construction surface?

 

My main reason for using grading objects is how easy it would be to modify the pond. I think the corridor might be a little more difficult to edit later on.

 

Also, Joe-Bouza, that is what I thought was my problem too. So, I made 100% sure that I used grading objects with all the same criteria. Smiley Sad

Message 11 of 15
neilyj666
in reply to: SMiddick

Gradings are notoriously buggy so be prepared for crashed drawings etc and be sure to save before modifying any grading objects

neilyj (No connection with Autodesk other than using the products in the real world)
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AEC Collection 2024 UKIE (mainly Civil 3D UKIE and IW)
Win 11 Pro x64, 1Tb Primary SSD, 1Tb Secondary SSD
64Gb RAM Intel(R) Xeon(R) W-11855M CPU @ 3.2GHz
NVIDIA RTX A5000 16Gb, Dual 27" Monitor, Dell Inspiron 7760
Message 12 of 15
Neilw_05
in reply to: SMiddick

Who knows why it is crashing, but why fight it? Go ahead and adjust the featureline. That way there won't be any discrepencies between your surface and your source data.

Neil Wilson (a.k.a. neilw)
AEC Collection/C3D 2024, LDT 2004, Power Civil v8i SS1
WIN 10 64 PRO

http://www.sec-landmgt.com
Message 13 of 15
MikeEvansUK
in reply to: SMiddick

Is the Controlling feature line in the same site as the grading group? If so try relocating to a new site.

 

Annother thing I find which makes feature lines fall over if the elevation points, if there are too many or sometimes they are too close then it can cause the grading to go haywire. Keep the points to an absolute minimum.

 

I tend to model a bit explode & export to a temp file because the more you use gradings the more you find the program locks and drops. Sometimes it's better to do most of the work in one file and recreate as a plain surface for production in annother.

 

Mike Evans

Civil3D 2022 English
Windows 7 Professional 64-bit
Intel(R) Core(TM) i7-3820 CPU @ 3.60GHz (8 CPUs), ~4.0GHz With 32768MB RAM, AMD FirePro V4900, Dedicated Memory: 984 MB, Shared Memory: 814 MB

Message 14 of 15
SMiddick
in reply to: SMiddick

I got this to work. And, it is fast enough that if I had to lower the pond bottom I would probably just remove the pond bottom feature line from the surface, lower the feature line, and then add the lowered feature line back to the surface definition. It just freaks out when I try to lower either the surface or the feature line. Locks up and never comes back.

 

All the suggestions are helpful though! I'm able to get the results I need. Thanks!

Message 15 of 15
losfotos
in reply to: SMiddick

Don't raise/lower the pond do it to the feature lines. Hopefully won't crash on you.

Carl Simpson
C3D 2015 & 2016

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