Needed: More Intelligent Divide Command

[KevinCollinsNEI]

I have been working on a site that requires me to create contours for a sloping surface that intersects with a benched highwall.  Because of the complexity of the geometry, I'm also being forced to layout the design countours by hand and then turn those contours into a Civil 3D surface.

The task that I find myself completing over and over throughout the design is creating a series of circles that divide a future breakline into several segments.  these circles provide me with two key locations.  First, it allows me to define the horizontal distance from the breakline for the nearest contour.  Second it provides me a way to locate the elevations of the future breakline.

If you'll look at the attached screenshot, you'll should be able to better iunderstand what I'm trying to say.

Each of the circles represent 1/10th of the distance between the design contours on the left-hand side of the breakline, the area on the left is sloping down to the south at 4% - countour interval is 2 feet - so each of those circles are 0.2' of lower in elevation as they progress down the screen.

Their radius defines the horizontal distance for the contours on the right-hand side.  The slope of the highwall on the right is 0.5 to 1, so each of the circles are .1 of a foot larger in diameter than the one above it.

Currently I create these circles using the following method:  I create a block - called tick - which is only a circle with a radius of 1 foot (large enough for me to see).  I use the "divide" command to divide the breakline segement (CYAN Line) into the required number of segements, placing the block at those division points.  I then manually adjust the radius and elevations of each circle using the properties panel.

As you can imagine, this is quite labor and time consuming.  So what I'm after is a better mouse trap.  If anyone know's a better way of doing this please let me know.  If not, would one of the LISP gurus here be able to code a better divide command that would automate the process?

Thanks in advance...

[troma]

I don't know what a benched highwall is, but I suspect there are easier ways to go about what you are doing.

Why are you building a surface from contours?  It seems like you are labouriously calculating contour intervals from a breakline, when it would be much easier (and more accurate and require less processing from the program) to just add the breakline to the surface and let C3D do its own interpolation.

Are you using 3D polyline or feature lines?

If you're looking for lisp gurus head over here. There are some really helpful folks hanging around.

[wfberry]

Without trying to understand what you are doing, I would suggest you use Feature Lines.  FLs can be adjusted with much more ease and efficiency than the Divide or the Measure command which are only AUTOCAD commands.

Bill

[AllenJessup]

I'm afraid that I have to agree with troma. I've never seen a situation where designing with contours wasn't the worst way to do it. Without any more information on what you're designing. I say, just draw the wall with Featurelines at the correct elevation or slope. Then draw a proposed groundline Featureline around the wall. Use that as a breakline in your proposed surface and as a mask for that surface.

Allen Jessup

[KevinCollinsNEI]

I agree with all of you - there has to be a better way of doing this, which is why I came to ask.  🙂

The reason that I'm doing it with contours is that I've tried the Civil 3D methods - Featurelines, Gradings, Corridors, the works.  None of them (even used in combination) can produce the final product the way that I can with this method.  I'm not even sure I can explain everything that is going on is this design and the reasons why Civil 3D's more flexible options simply aren't working in a forum post, but I'll sum it up by saying that my knowledge of Civil 3D's capabilities has been exhausted looking for a "proper" way of doing this, so I've have to fall back on manual means.

Here's one of the cross sections from the design (unfinshed, but you'll get the idea):

The green line is existing ground, the red line is the proposed regrade on the side.  The line that will become the breakline (the cyan line from the first image) is the intersection of the cut on the right side of the section and the first steep slope of the highwall.  That intersection is, for lack of a better description, like the flowline of a ditch, sloping down at 4%, so at every section that intersection is at a different elevation.  However the benches are not sloping, they remain at a constant elevation.

Does that help - make it clear as mud?  🙂

[Joe-Bouza]

Also, a grading object should be able to handle the divided transition you are laying out. From you image it looks fairlt straight forward to create a distance slope transition.

[KevinCollinsNEI]

And just to complete the picture, here's a plan view

[fcernst]

If anyone know's a better way of doing this please let me know.

Yes definitely.  Use a Corridor with an Offset assembly at the toe of the Benched Wall to address the meandering Benched Wall alignment.

[jmayo-EE]

I also agree there are better ways to tackle your task but to help get through this,

1. Make the benched highwall a Fline as others have suggested. Assign key elevations and/or design grades to start and end points at a minimum (QuickElevationEdit, Set Grade/SlopeBetween Points or Elevation Editor as needed).

2. Use the stepped offset command to create another FLine a unit or so away from the original at the same elev (or a projected grade if you like).

3. Chuck both of these into a surface with contours displayed and you will see exactly where the contours project.

Sometimes a boss provides a redlined map with proposed contours and that is the only thing they want to see you working on...drafting the contours that they spent time interpolating through the site. You need to convince them to stop drawing contours and ask them to give you a map with only key elevations and grades so you can build the model and see where the contours lie. Assign proposed grades to the objects you are building. This will same both of you time.

I can think of two situations where I typically do resort to contour design. Ponds/lakes because of highly irregular shapes and varying grades that lie under water and golf courses which do require a lot of flat areas to be shaped or sculpted with relative precision.

[brian.strandberg]

I agree with above for creating your surface, as for a more intelegent divide command, I recomend ARRAYPATH.

http://docs.autodesk.com/ACD/2013/ENU/files/GUID-D36C46CD-4E17-4A16-A387-C0B158EA5A9E.htm

[AllenJessup]

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@Anonymous wrote:

 You need to convince them to stop drawing contours and ask them to give you a map with only key elevations and grades so you can build the model and see where the contours lie. Assign proposed grades to the objects you are building. This will same both of you time.

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Amen to that!!

I do sometimes use contours in design if you consider a featureline at a single even elevation a contour. I have used them as breaklines to regularize contours in some situations.

[sboon]

Very interesting.  This command looks like it might be a solution for a question from another thread, about running stationing labels along  the 3d path of a pipeline.

[fcernst]

Elevations from a hand drawn redlined map may not even be so "key" from someone doing hand interpolations when trying to correlate into C3D and a dgitial terrain model.

I suggest let's be the C3D designer your company is looking for you to be..

Workflow:

Get all the design contraints from your engineer, and you show them how the benched wall system fits per that criteria into the topographic model that will also be used for staking.

Use the redlined map as your conceptual guide. Give them a preliminary effort to comment on.

For example, typical constraints for this: 

• Max and Min allowable heights for walls (perhaps conceptual desired wall heights also)
• Min width of benching
• Max min slope of benching
• Cant (pitch) of wall system (per manufacturer)
• Model adjustments to meet earthwork requirements.

[KevinCollinsNEI]

Sorry for taking so long to get back with you folks - work has gotten crazy.

Anyway - I've tried to use both corridors and gradings in conjunction with feature lines and have had little to no luck.  So, what I have done is clean the drawing up so that only the existing ground surface and the feature line that represents the toe of the highwall is present.  I've also added a couple of sections that would represent the finished highwall and a few notes and dimentions to help guide things.

If you guys are willing, can you please look at the drawing that I've attached and try to create the highwall - once you figure out your method, let us all know.

My attempts have failed because the cooridor wants to follow the slope assigned by the feature line, I can't get Civil 3D to understand that I want the benches to be at a certain elevations and the cutslope between the toe and first bench is to change.  In another attempt - when I just let the benches slope, the tie-points to EG were..less than clean.  Gradings, at least in my mind and realm of knowledge, won't work in this scenario.

I hope that I've explained it well enough to get us started...please let me know if there is anything else that I can provide to help.

EDIT:  Since the drawing is too large to attach here (really 1.5 MB Autodesk?  This is the 21st century you know...), I've uploaded it to my dropbox account.  Here is the link to download it.  It's a bit over 5MB in size.

[troma]

I'm not a corridor or gradings guru, and I didn't look at the drawing.  But I imagine that what you're attempting can be done if you have your targets set up correctly.  You can target a profile or alignment, or a feature line or polyline, or just a set elevation.

If corridors or gradings really don't work for you, just use feature lines.  Every breakline needs a feature line.  Every top of slope, bottom of slope, front of step, back of step.  This method is totally flexible.  If you can't do it this way, I don't know why not.

Of course, just using feature lines isn't as slick as corridors or gradings.  But it's definitely better than the way you were designing before! (really contours?  This is the 21st century you know...) 

[ArchD]

So your goal is to find the intersection of two surfaces?

If so, create a surface style for intersections, and in the display tab of the surface style, turn on User Contours.

Once you have the style, create a TIN Volume surface that uses the Existing Ground Surface and the Proposed Grading Surface.

Then, in the surface propperties for that new surface set the style to the intersection style then go to the Analysis tab and add one User-defined countor at elevation 0.

This will give you the intersection of the two surfaces. Extract the user-defined contour. Once you do so, it'll be duplicated, delete one and you'll be left with one contour that will be at elevation 0. Turn it into a feature line on a temp site and set the elevations to either one of the surfaces that were used for the interesection.

One you do this, you will have a line where the two surfaces intersect at the correct elevation.

Here is an example