Terrain and topography modeling

Hi all.
I’ve been using SU for a while to model some furniture projects, mostly square units. I’m currently working on rearranging my garden. It’s now a hill, with approx. 2:1 - 3:1 downhill slope. I’ve had some landscape architect make some drawings, and he has included some leveled spaces on different heights throughout the hillside. I now want to model this is SU, and I’m running into some issues. I have used the contour lines from his proposal to make the landscape using the sandbox from contour-line option. Then I have stamped in the leveled areas into the model. The terrain uphill of these leveled areas are supported by concrete walls of different height. When I include these walls in the model, there is a “ditch” between the wall and the existin terrain. I’m struggeling to make the terrain uphill of the wall “adapt” to the wall I’ve drawn in. If anyone has experience in doing this or can provide me with some tips, I would be very thankful.

Any chance you have an image or SketchUp file to share?

I know you were trying to be descriptive in your initial post, but without any context, it is really hard to picture what you are talking about. The more info you can provide, the more likely someone here will be able to help you out!

Thanks for the reply. After posting, I found a “site grading webinar” online, and watched through it. Turns out I kinda started in the wrong end by trying to model something onto an already created landscape rather than making the flat surfaces and retaining walls first, and then add the landscape afterwards.

Link to the video I watched is SketchUp Introduction to Site Grading
Highly recommended.

Note that the “Sandbox” tools in SketchUp cannot create plumb vertical surfaces:

  • the “From Contours” tool skips contours that are directly below other contours
  • the sides of the flat areas created by the Stamp tool are always sloped (it doesn’t accept “0” as the offset value.

Anssi