Conditional subassembly for road shoulder
Hi @Ingrid91, I hope you are doing well. I read your post and I have a few questions before I can suggest something.
1. Where is measured the slope of the shoulder you mentioned? At 1 or 2? (see image)
Another question: How do you determine the regions where the shoulder must have either less or more than a 5% slope? Depending on what? Is it going to be different whether it is in cut or fill condition?
The three conditions you mentioned in your post end with a daylight slope that targets the existing ground. Then what would be the difference between them? The slope of the daylight?
Could you please provide an answer to these questions to better understand what you are looking for? Try to provide a cross-section sketch for the three conditions.
Best regards!
Camilo Fernández
P.Eng | Transportation
I might add, the daylight slope belonging to the shoulder is set to 4:1. The daylight slope (or another word for it?) that I want to reach the existing ground is a separate subassembly from the shoulder subassembly.
1. The shoulder slope is determined by the yellow arrow in attached image (or number 1 according to your image).
2. The shoulder slope should be determined by if it can't reach the existing surface within -5% - 5% range and predetermined width A that a daylight slope is required
3. The difference between the conditions is the cut/fill slope of the shoulder and consequently the slope of the daylight searching for the existing surface within a predetermined width A
If this is something that can't be set up in C3D then I'll have to manually adjust it after exporting cross sections.
Hi @Ingrid91, So, I understand that the shoulder should stick to the ground if its slope, measured between its point of origin and the terrain, is between -5% and 5%. Conversely, if the same slope is greater than 5% or less than -5%, then, the shoulder should be created with its normal slope (4:1) without sticking its edge to the terrain.
In this context, I cannot think of a way to do this directly in Autodesk Civil 3D. However, I know this behavior can be programmed with Autodesk Subassembly Composer. Check the attached PKT file (uncompress and import it to C3D). In the subassembly, I simulate the slope between the point of origin (the point where the shoulder is attached) and the terrain to know its slope value before assigning it to the shoulder. Then, I evaluate the slope value to know if the final geometry has to stick to the terrain or be drawn with its normal 4:1 slope.
These are the preview pictures in Subassembly Composer
Give it a look and let me know if that is what you want.
Best regards!
Camilo Fernández
P.Eng | Transportation
Hi Ingird,
Thank you for submitting your question in our discussion forums. I see you are visiting as a new member of the Civil 3D forum. Welcome to the Autodesk Community! Have you had a chance to look over the suggestions provided by Camilo?
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Hi @ektkamv the problem might be I worked with Subassembly Composer 2025. Which version are you using?
regards!
Camilo Fernández
P.Eng | Transportation
Hi @ektkamv, unfortunately I don't have any other version of Civil 3D. See the following images so you can replicate the logic branches of the subassembly
Slope evaluation variable
Decision evaluation
P2 sticks to the ground when slope between minus5and5
To the side of Minor than5 or over5
Input parameters
Target Parameters
I hope this helps. Best regards!
Camilo Fernández
P.Eng | Transportation
Well, an amendment to the text you've written.
"So, I understand that the shoulder should stick to the ground if its slope, measured between its point of origin and the terrain, is between -5% and 5%." Yes. And the shoulder slope is the "outside slope shoulder" S2 (see picture below).
"Conversely, if the same slope is greater than 5% or less than -5%, then, the shoulder should be created with its normal slope (4:1) without sticking its edge to the terrain." No. The shoulder slope should, in the case it is greater than 5% or less than -5%, stop at 5% or -5%. The shoulder slope is the "outside slope shoulder" S2. The daylight slope 2 that is always connected to the shoulder assembly is only going to be 4:1 slope (because of the narrow space for cut).
The daylight slope X that is added to the shoulder assembly is only applicable when the shoulder slope is greater than 5% or less than -5%, and therefore stops at 5% or -5%. The daylight slope X is varied but searches to the existing surface. Would be neat to be able to use a "width target offset" for it.
The daylight slope X is new grass.
As for the pictures of how it looked in the program you used to define them... I'm sorry but I really don't know how to interpret them. You're talking to someone who's never used Autodesk Subassembly Composer.
