Transition parabolic superelvation cross section

[karen.chalkley]

Is it possible in civil 3d to input a cross section of superelevation as parabolic rather than straight section in civil 3d. We are looking at a parabolic bend of 40 degrees.

Much appreciated for your help.

[peterfunkautodesk]

Is the blend in cross section or along the alignment? A picture would help.

Cheers,

Peter Funk

Autodesk, Inc.

[karen.chalkley]

Peter,

The parabolic shape is in the cross section See the attached file. I beleive the parabolic shape in the alignment is an automated feature if you choose this option while creating alignment curves.

Currently,  I caluclate the points on say 5m intervals manually along the cross section to get the data for the prabolic shape. But would be handy if this can be inputted into civil 3d.

Thanks.

[peterfunkautodesk]

Interesting....

Out of the box we don't have a road section that was designed to superelevate to 35% with a parabola. However, take a look at Subassembly Composer. You can add parabolic curves in there between two points. Set one point at the inside edge of the track and the second point using Slope and Delta X where the slope is the superelevation. Then add a Curve between the two points. I was playing around and a Mid-Ordinate Distance of 1 looks pretty good, but I'm not sure how that works for your geometry. I also wasn't sure if the whole track gets curved or only the outer edge. If you know the math that is used to make the track cross section, you might want to use the API to make the calculations directly.

Cheers,

Peter Funk

Autodesk, Inc.

[karen.chalkley]

Thanks peter. Ill have a look at the sub-assembly composer. Not much of a user of it but will give it a try. If it does not work will have to stick to the old method of prodcuing results through calculations.

Much appreciate with the help.

[sboon]

Now I'm really curious.  What the heck are you designing that needs a 35% superelevation?

Steve
Please use the Accept as Solution or Kudo buttons when appropriate

[fcernst]

[vantamuct]

Hi Fcernst. Are you still there? I have the same problem with the topic, can you share your works (Civil 3D file, specification, related documents). Thanks in advance!

(Vantamuct@outlook.com.vn)