multiple surfaces lowest elevations

[gelinase]

Hi,

I have many surfaces overlapping and I want to create one surface with the lowest elevation for each x,y coordinate from the existing surfaces. Does autocad civil 3D have a command who can help me?

Thanks.

[Joe-Bouza · Accepted solution]

This sounds like Dejavu all overagain.

If you make volmume surfaces you can extract the zero contours to use as boudaries to the lower surfaces. I would expect to see a jigsaw puzzle that dovetails together. The make a new surface"combined and paste all the "Cut" areas into combined.

[gelinase]

like this post:

http://forums.autodesk.com/t5/AutoCAD-Civil-3D/Creating-Lowest-Surface/m-p/3428837/highlight/true#M1...

thanks

[Civil_Engineer_In_Irvine]

Yes like that post...... which I watch every day in hopes of a better way.

It is very tedious work if you have a lot of survey and surface information.

Should be done congruently with the survey

[scottlaw75]

I have been looking for a realistic solution to this for years.  I often times have multiple surfaces (maybe as many as 10) that need to be compared and have the as-built bottom created for.  We have a few people with carlson software that can do this, and have been for years, and Autodesk still sadly lacks in this area.  I really wish Autodesk would spend more time on improving grading related additions to the civil 3d software for people like me that don;t use the piping and corridors all day.  It's a love/hate thing for me with Civil 3D.  🙂

[tcorey]

If you would like to contact me directly, tcorey at Shasta dot com, I have a LISP routine that will write the points to a file or place COGO points in the drawing, with the point description = to the name of the surface that is the source of the lowest point among selected surfaces. It's just about exactly what you asked for.

[scottlaw75]

Thanks Tim, I will attempt to contact you to further discuss this topic.  Multiple surface comparison seems like a pretty standard thing for anyone on the mining industry and Autodesk really seemed to have let the earthwork portion of their product stay stagnant for years now sadly.  I make do with what we have but I still have to use other software work-around in order to get pretty basic stuff I would love to do on my own within my own Civil 3D workflow.

[nando.dilorenzo]

Hi

Which command or menu is Create a composite bottom surface in Carlson software?