AutoCAD Civil 3D

[#1]

I'm wanting to make a corridor model from an imported DGN that contains centerlines and edges of pavement for a neighborhood.  From 2011 and 2012, the import creates splines while 2010 and older create 3d polylines.  

The alignment creation from objects does not work on a 3d polyline or spline and I have no clue how to make a profile from the same object.  How could I go about making an alignment and profile from a 3d spline or 3d polyline?  Seems like that should be something simple, yet I'm stumped.

[#2]

Here's a quick way to solve your issue, at least with 3D polylines. I have not tested with splines, but I think it will not work:

http://screencast.com/t/fatZxtxldO

Best regards,

Tim

[#3]

I would love to watch that video but our idiotic IT masters block screencast so I have no way to view it.

[#4]

Sorry, that's the only place I saved it, so I can't email it to you. Maybe you can get the IT Nazis to give you special permission for three minutes and thirty-six seconds. I will give them my personal guarantee that it's not porn.

Tim

[#5 · Accepted solution]

I can't get this to work for a spline, but for a 3d polyline an easy way to make an alignment and profile is to make a "Quick Profile" from the profile dropdown, make sure you select the "draw 3d entity profile" box.  Then under the file menu select Export -> Export to LandXML.  The press the uncheck everything button.  Then use the select button to just select your profile.  This will export an alignment and a profile to an xml file.   Just reimport it and you are good to go.

So in summary, quick profile, export it to land xml, reimport it.  I attached a few pics.

[#6]

Nice, straight-forward solution.

[#7]

Thanks for the information!  I did end up getting to watch the video by using my boss' Galaxy Tab 10.1.  I am going to try the other method mentioned about the quick profile and LandXML method. 

Seems like there should be a much easier way to use a 3d spline/polyline to accomplish the same task.  In fact, I think having a 3d polyline or spline would be much better and easier to use as a baseline in a corridor than the two separate entities of alignments and profiles.  I know that's how road design has been done for eons, but internally it would be so much easier to program and just do a type of sweep/loft along a path similar to how 3ds Max could do a road.

Oh well, back to work.  Thanks again.

[#8]

I agree, and it seems like C3d is so close to being able to do this.  You can make an alignment and profile from a corridor feature line so why not from a regular feature line?  You should be able to just convert your 3d polys (or maybe splines) to a feature line and press a button. 

I know it would make my life easier...

[#9]

Found this tip on using the flatten command to get a polyline with arc's from a spline no z  throu.

http://lynn.blogs.com/lynn_allens_blog/2011/07/an-autocad-hip-tip-on-turning-splines-into-plines.htm...

[#10]

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engrtech wrote:

Seems like there should be a much easier way to use a 3d spline/polyline to accomplish the same task.  In fact, I think having a 3d polyline or spline would be much better and easier to use as a baseline in a corridor than the two separate entities of alignments and profiles.  I know that's how road design has been done for eons, but internally it would be so much easier to program and just do a type of sweep/loft along a path similar to how 3ds Max could do a road.

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The problem with that is we typically Engineer things in the Civil world.  And for that, it is by far easier to use the 2-1/2D paradigm (e.g. horizontal layout + elevation) vs. a true 3D paradigm.  Artists and machinests find it easier to use the true 3D, but when it comes to a construction project, true 3D can greatly increase the complexity while not really helping.

Same thing with splines, even in 2D.  They're a lot more complex a geometric figure, and make land work much more difficult.  There's the raliway and highway curves, but those tend to be described in a rather simplified form that limits options, and makes it possible for computers (including calculators, data collectors, smart phones, etc.) to do those calcs with a minimum of input.  Using free-form 3D splines makes for a lot more complicated possibilities, creating difficulty for everyone who must then build your design.