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Creating a surface model in Civil 3D from existing 3D polylines, lines and points


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Hi all,


I'm quite new to Civil 3D and I've tried to have a look online to find what I'm looking for but I feel it might be easier to just ask.


I'm wanting to generate a surface model of a complex feature survey which I currently have in AutoCad. All the 3D linework for kerbs, retaining walls, footpaths etc. as well as spot heights are already in the AutoCad file (due to the nature of the project the workflow isn't very nice and predominantly involves DXFs which are then stitched into the main file and the layers are adjusted afterwards). I don't have any codes or data input workflows setup within Civil 3D. I have another survey software package that I normally use to generate my surface models but it will be very time consuming to import the DWG and set it up beforehand due to the scale and amount of breaklines so I was curious if it would be easier for me to try and do it in Civil 3D (it might not).


How easy is it to take 3D polylines, splines, lines and points from a DWG and generate a surface in Civil 3D? Is it possible to select all the lines and ensure they are breaklines? Are you able to make select layers non-contourable? How easy is it to generate model boundaries?


I would greatly appreciate any guidance.






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First, create the surface in the Prospector (which is in your Toolspace). To do this, right-click on Surfaces and select Create Surface. You don't add any information to it in this step, just give it a name.


Second, expand the Definition for the surface (still in your Prospector). You'll see a list of object types you can add to the surface, such as points, contours, and breaklines. Select the points (for instance) you want to use, right-click on the Points item, and tell it to Add. Do the same for breaklines or whatever else you need. If the items you need to add are on different layers, it may help to isolate them before you select.


Don't worry about getting your surface exactly right on the first try. You can always close the drawing without saving (you saved first, right?) or edit the surface afterward. To get a look at the surface itself, select it and use the 3DORBIT command.


You'll probably have questions. We''re here to help.

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You may have to resort like CyberAngle to make points for all the vertices of the objects, like 3dpolys, Lines etc, the spline need to make points along the spline else will not represent the shape.. This will allow read of all 3D points into a surface, you will then need to add breaklines. Your surface should then be correct. 


If as suggested you have contours but it sounds like these again are actually plines hopefully with an elevation. If they are at RL 0.0 but labelled then can move to correct Z then make points, not easy to automate.


Do you have anything to add 3dpoints to objects ?

Edited by BIGAL
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