Topic: Feature Lines/Break Lines

[dfarris75]

I'm curious how everyone else (civil engineers & assoc. cadd'rs) goes about creating eg breaklines for an eg surface when they are not supplied by the surveyor.
What would be the most efficient way to create my eg breaklines? Manually draw them? Copy the existing linework and convert to feature lines then adjust elevs? Other?
Please enlighten me.

[mjfarrell]

Queries:

If said 'break lines' are NOT provided by the surveyor, how is anyone else ever going to accurately represent what was there?

If the surveyor will not provide break lines will they at least provide a surface in either XML or TIN format?

Any breaklines that you add will be your best guess at best. If you use Standard or Proximity as your type the truth is in the end you are guessing.


Here let me look http://en.wikipedia.org/wiki/Civil_engineering, nope the phrase "guessing what an existing surface is comprised of" isn't anywhere in there.

You may need to contact the owner and or surveyor and ask that they provide A) all of the data from their survey, break lines included, or B) LandXML of the surface, and or a TIN file, or C) all of the above.  Otherwise you have entered into the realm of guessing, not survey or engineering.

[dfarris75]

Well since we're in the realm of guessing at present what it the most efficient means of guessing the breaklines into a surface?

[mjfarrell]

Convert the objects into Feature lines, and assign elevations to them from the surface, do not add the intermediate grade breaks, and then add as as breaklines.  I would use extreme prejudice in doing this, if for instance you have a(n) active Quick Profile going and the surface appears OK without you adding your best guesses to it, then leave it alone.
From looking at it yesterday there seemed to be enough data that the quick sections looked reasonable. (Remember though I haven't seen the site, nor did I examine all of that surface.)

When you create the Feature Lines and the Break Lines from them be sure to name them so that everyone knows where they came from, and describe them explicitly.

[dfarris75]

Understood. It's a pretty flat site. I've already removed all of the troublesome points that caused spikes or holes and it does look decent. This is one of the better surveyors we use.

[mjfarrell]

Please have them contact me; as I would so much enjoy helping them out and their clients would sure enjoy the cost savings of NOT building the EG twice.