Create a slab from contours - 3D polylines

[jh75]

Hi,
I need to create a slab that has contours. The contours are not to "complex" and I have them as 3D polylines with a z value. I know I can import the contours and get a surface but I would like to able to create a slab ie "a surface" with a thickness.

Are there any ways of doing this or am I better of trying to generate the slab in autocad and the bring it in to Revit as component?

Thanks,

J

[Ben-May]

You will only get a slab line if the slab changes grade, you should be able to get this to work in principle if you bring in a 3D DWG and create slab split lines to match the DWG and then snap the points to the 3D drawing, it obviously wont really work for curved lines which is probably what you want

Otherwise I would look at creating the ramp and possibly using model lines to represent to contours on the slab surface

[JCM]

Couldn't he overlay the dwg with the contour lines and then modify the floor sub-elements and add points to correspond to the overlay and then change the height to match such lines? Making sure that the floor has he top layer has the variable check activated unless that is not a concern.

[jh75]

Yes the contours are curved. At the moment I have modelled the slab and then used "sub-elements" to create a new point at each end of the contour line and one point in the middle of the contour line.
The result is OK but it would we great to be able to draw curved split lines to mimic contours

Cheers,
J

[JCM]

Yeah Revit and Topography tools are still in their infancy imho. 2014 anyone??

[Karalon10]

I had to create something similar to what you are trying out there for a basement ramp that had a curved blend on the end of it, with both fall and crossfall.

I just modelled it as a slab, for me I could get away with a mass concrete piece but this should also work for what you need although it did take a bit of mucking about.

As you said, using sub-elements in a slab is the best way, and if you have contour points that makes it easy as you know the value to set in and where the contour point should cross your element also. I think you will find the slab sub-element method the best for now I tried several other ways and they just didn't really give a good result. Make sure you set your slab depth to be non variable under the "structure" tab of that element. If you don't want to see the linework of the cross falls go into your visibility graphics and one of the settings under "floors" will hide those lines for you. I forget which exactly and I dont have revit open to check for you, for some reason hidden lines comes to mind but I don't think thats the one you want. Internal edges maybe? Anyways, try those settings out and you wont see those annoying fall lines in your slabs.

[jh75]

Hi,

I had a brief moment last night to look at creating mass objects - something I haven't touch before.
It looks like you might be able to create a nice surface from using "spline through points"

You draw lines and add an elevation to the points on the lines. Then select all the curves and go to Create Form. I am still stuck at how do join all the ends of the splines together to create the outline of the mass object.

J

[jh75]

What I was struggling with was to with the penetrations for the ramps. I drew the penetrations when sketching the slab outlines. The problem I had then was to add points at each side of the penetrations and along the edge of the ramps. After a good night sleep I decided to model the whole slab and then use opening by face instead. So far it seems to be a much easier approach.

J

[Ben-May]

What I was struggling with was to with the penetrations for the ramps. I drew the penetrations when sketching the slab outlines. The problem I had then was to add points at each side of the penetrations and along the edge of the ramps. After a good night sleep I decided to model the whole slab and then use opening by face instead. So far it seems to be a much easier approach.

J

You can just add the penos with a vertical opening which will result in the slab remaining without additional points at the opening.