contour creation from a Tin surface import

[mattV87CE]

Good morning All!

  I just created a surface in Revit from an 3d exported tin file. I created the surface easy and is showing up as a 3d tin surface in revit. I am trying to fig out if revit can add the contour lines to look like a standard topo surface? or will I have to take the 2d cad file and manually create a surface by giving each individual line its true elevation. Our CAD package is ACAD 2019LT & Revit 2019LT. Is there is a way to make the surface appear more realistic besides the view templates? I have been searching and not have found anything specific. I will play around with the view templates to see what other options i can fig out.

Thank you in advance!

[SteveKStafford]

Have a look at Site Settings and define the elevation range for the topography. There are primary and secondary contours and you can define where they should be represented. For example the topography might be at 454' above sea level. You can start generating contours at 400 and stop at 500 using secondary contours at 2' intervals while the primary contours are at 5'.

Keep in mind that Revit's contours will be influenced by its own logic for distributing points according to the TIN. Once the surface is created you can add points or remove them to adjust the appearance of the contours. Use the same resolution as the source to get contours as close to what the survey is as possible. There will be differences though. You can fine tune it (contour path) to some degree by adding/subtracting points slightly above and below known points.

Also if the survey data collection was based on 5' intervals Revit will interpolate what secondary contours ought to be by placing the contours between the points defined in the source file. In other words you can use a higher resolution than the source data provided but it won't be accurate because you don't really have that data to make it so.

[mattV87CE]

thank you, that got my contours to show up, but I have a bigger units issue i need to look at. think the cad file i imported was in inches or something

[SteveKStafford]

Civil files are often using Feet as the base unit but I find many landscaping people use Inches. If Revit doesn't guess correctly using Auto then specify the units instead. You can also change the units after importing, it is a type parameter for the file but its location will shift when you change the units. For example if the file is much too small, change it to Feet and then reset the Scale Factor value to 1.

[mattV87CE]

thank you, thats what i did, changed it in the cad file prior to import. Now figuring out the insertion point vs civil coordinates as the cad file was created in a random location. Appreciate the help Sir!

[SteveKStafford]

Backing up a bit...

Import the survey data using positioning Auto - Center to Center - this puts the survey elements near the Revit model's internal origin which is what Revit wants us to do so the math is easy.

To align the Revit Survey Coordinate System with the survey source World Coordinate System you can use Acquire Coordinates. This will shift the Survey Point icon to mark that location (probably quite far from the Revit project origin, Project Base Point). Once this is done an export to DWG using the Shared Coordinates option will result in a Revit exported DWG that aligns with the survey source file when it is externally referenced using Origin to Origin.

Now you can choose to create a building model over the site, in this model or a separate building model file that can be linked to this one (site). If linked you can move the building, rotate it and raise it up to the correct ground floor elevation. Then Publish Coordinates can be used to pass along the survey coordinate information (as well as rotation/elevation) to the building model. In the building model plan views can be assigned to True North or Project North (default orientation) so you can see the site conditions (site model can also be linked to the building using positioning By Shared Coordinates).