Grading - adding new grading objects makes old ones disappear

[lohrmach]

I'm Grading a somewhat complex and constricted site. Feature lines are mainly drainage channel centerlines and I'm Grading up (slopes and terraces) from there.

I add the channel bottom, side slopes, then sometimes grade to surface on the outside (seems to be problematic).
I also do not grade entire object length every time (also seems to be problematic).

I can't find a consistent rhyme or reason to this (yet), but when I grade something on one side of my feature line - obects on the other side of my feature line that I have already graded disappear. Where I once had a surface (grading lines, surface elevations, slope arrows - for automatic surface generation) - I no longer have a surface there. The grading object seems to have disappeared.

But most often times - remnants of the grading objects are left. Like outside slope lines from grade to surface or grade distance and slope. In my previous drawing (before creating a new one hoping it would eliminate some of these problems / also my design had changed significantly requiring new channel alignments) - I had to put these objects on a frozen junk layer because deleting them would often crash the program.

Civil 3D Grading is the main crux of what I'm depending on to design this project and I'm hitting delays repeatedly. I've generally been able to control the problems by deleting gradings and re-doing, but I need these grade to surface gradings in the end and they just don't seem to work. Even now when I know they grade onto the existing surface. Even when they work - they disappear with no warning.

New Discovery: My feauture line is my channel centerline. It is a trapezoidal flat bottom channel. I grade one side of it - 2' flat bottom level, then a side slope up. I grade the other side of the flat bottom. All appears fine. I try grading the other side side slope up on this side. When I do that - Civil 3D eliminates that entire side of the grading from my graded surface - I still see the Grading lines, but there are no elevations for surface / no longer in the boundary / no slope arrows. When I delete this last part - the 2nd side slope, it actually turns the adjacent flat bottom side that was eliminated from the surface with the previous command BACK into part of the surface again. It looks like a BUG. But I can't figure out more than this right now. Edited by: lohrmach on Sep 11, 2009 11:23 AM

[HC1975]

Did you find a solution or workaround?

-HC

[idmadcadder]

I have also had this happen on a project, and it is a real pain in the ass. Taking a lot of time to redo grading because it disappears. I never did find the cause of it.

Brent Daley
Civil Designer/CAD Services Manager
The Land Group, Inc.

[lohrmach]

Work-around. Not ideal, but MUCH more reliable and the way I will do Grading from now on:

Not creating Feature Lines, not creating Gradings.

Instead: using 3D polylines & 3D offsets (Grading - Feature Line - Stepped Offset). My grading design completely depends on being able to create 3D offsets. It's a lagoon closure - like a landfill - with slopes, terraces, and channels.

So I'm basically not using the Civil 3D tools the way there were intended to be used at all & I give Civil 3D Grading an "F" for Fail from my experience. My current method is nearly identical to how I graded projects in Land Desktop and Eagle Point.

What I need is Reliable. Reliability is the most important feature that I need.

I am using Gradings around the outside of my design to slope to Existing Grade - still touchy, but I can't find a fast and reliable way around needing this.

[andrewpuller3811]

Yes, gradings are a major pain due to their instability.

Sometimes they work as advertised, but most of the time there is some sort of problem.

I had a similar problem occur in a job recently inwhich I was grading a detention pond, the first 2 gradings worked fine but the third would cause the second to disappear.

I managed to get it to work together by putting in the first 2 then copying the featurelines around the edge of the first and second grading to a new site and hanging the third grading off those in the new site. Not ideal as I have duplicate featurelines, but I get my gradings to work together.

It may be possible to tie the duplicate featurelines together to keep everything dynamic and linked, but I haven't had a chance to try this out.

[BrianHailey]

As I don't do design any more, I'm talking from limited experience pounding on a project month after month. I usually go into a clients office, help them out for a bit, and then I don't deal with that project anymore.

With that disclaimer, here are my thoughts:

I've heard to many horror stories like those stated here but I have yet to run into them myself. I personally love feature lines and wouldn't even consider designing a site without them. The only time I would use the grading tools (i.e. projection grading) would be when I need to tie into a surface. As stated earlier, the other grading methods can easily be recreated by using the stepped offset command. I prefer feature lines over 3d polys for several reasons. First, they interact with each other. If I change the elevation of a feature line, any other feature lines that cross it will change too. Second, they have some great editing tools that aren't available for 3d polylines. Third, they can have curves.

Hope this helps.

Brian Hailey
http://www.cad-1.com
http://www.AtYourDeskTraining.com

[Yellow600]

Has anyone found a solution.  It has been a few years since this was posted but I am having the same issue in Civil 2014.  I have an alignment that i turned into a feature line to hold my ditch profile.  I graded to distance at 2 ft on each side creating a 4ft ditch bottom.  I then grade to surface using a 4:1 on one side and eveything looks great.  then i go to the otherside and it all disappears.... I got it to work by creating two sites one for left side grading and one for right. it works and i get my surface but if it keep it in one side and grading tool i get the same issue this user had.  In the past i have used cooridors and it worked ok but this would be much easier for many of my applications if it worked correctly.  I've spent a while trying to figure it out and I think I'm going to leave it since i got it and move on for now.  THOUGHTS??

Thanks in advance!

JON

[joesmoe19]

I am also having this issue with grading objects and their associated feature lines disappearing in C3d 2013.  It seems to happen more with grading objects than just using features lines without the tools of a grading object.  It feels like working in circles having to recreating the grading for complicated site with tight deadlines is a significant issue.

Anyone have any real solutions?

Joe

[ChrisRS]

Well guys, I am using Civil 3D 2018 and still see the same behavior as @lohrmach described almost 8 years ago.

You all might want to review my post on the Civil 3D Ideas page. If you concur, please vote it up:

Fix "Grading Objects" or admit defeat and identify the replacement workflow

I recently when to my VAR with a support request on this. The initial response was that my original drawing was probably corrupt, but they did agree to a skype session where we started from the stock OOTB Imperial template and created some grading objects. The process quickly broke down. They suggested some work-arounds, but were of the opinion that linking gradings and using transitions was beyond the stability limits of grading objects, even though that is how they are supposed to work. This has been escalated to Autodesk; I will post an update if I hear from Autodesk.