Importing one model into another model

I have a model of a bridge that need to go into another model that shows a terrain and a road which will be constructed. This is where the bridge need to go:

I used stamp tool to put my road on the terrain and now I have problems putting the bridge in its right location because there is a surface that if I delete it, all terrain gets deleted.
I need to show that there is a valley in the location shown with red arrow so the bridge I designed can fit there perfectly to see the impact of the bridge finally. How I solve this please?

This is the bridge model:
Via derilio.skp (1.1 MB)

This is the terrain model:
All contours_5m_terrain.skp (6.7 MB)

You can use File> Import and insert your bridge model. Then rebuild the terrain in the area below it and remodel it.

terrain-bridge.skp (7.8 MB)

But keep in mind that in reality the road would have been built in a different way, closer to how I showed you in the first Gifs of the other discussion.

You skipped a lot of learning steps. Try to follow these tutorials for beginners:


Thanks so much @mihai.s. This file is exactly what I need. You placed it perfectly and deleted all the stamped surfaces from under the bridge. I think I should build the terrain based on the road again.
Yes unfortunately I had to deliver a work urgently and did not have time to learn the software from the basics. I just tried to find a workflow to have some results for my boss.
Thanks for your help again.

You’re welcome!

Look at this model, I modeled the bridge and the road follows the terrain line - road_stamp-v2(SU2017).skp (2.8 MB)

1 Like

yesssssss that’s exactly what I need. How can I achieve this? :grinning:
I need to do it for other bridges. You did not make the terrain yourself here?
I wish I could learn from you

By learning and modeling… a lot! And you of course to be interested on this domain.

Import the other bridges and position them, using Move and Rotate tools, and Arrows for constraints on axes.

What your boss gave you to do is not a job for beginners. (tell him that!)


Yes, you are right. This task is not simple and it’s not in our domain of work.
My boss does not now anything about this stuff. He keeps telling me it’s not difficult and why I have not finished yet! He just told me he wants 3D rendering of these bridges on this road. So even after this steps I have to find another software like VRay or one ray to make this model look like reality

An improved version as an example - road_stamp_v4.skp (4.5 MB)

It is probably best to:

  • draw the center of the road on the terrain;
  • position all the bridges in their place using the ‘center line’;
  • adjust that line to be as smooth (on Z) as possible and to fit each end of the bridge;
  • then build the road.



Dear Mihai,

I tried to use your beautiful design but my boss says the road is moving so much up and down and in reality it will be more straight.
So, I imported the center line and positioned all bridges. The bridges show a slope in their design and the center line does not get matched on both sides of the bridges. My idea was to use Smoove tool to fix the terrain under the road but now I cannot solve even the slope of the line! Would you please take a look at this file?

Road_bridges.skp (7.3 MB)

If your boss’s statement is based on the data of project of a road with level elevations, then maybe so be it and the road is flat from head to tail.

But at what level differences appear on the entire route of the road and at what types of bridges appear in your model, I think that the road is not flat and follows the forms of relief.

You positioned the bridges ok, you just have to fit them at ground level and then build the road at their level, following the terrain (with small straightening of it).

It’s normal that the flat road does not match the types of bridges you have, because they are designed for a road that follows the shape of the terrain, not a flat road for 3 km. You can’t find such a road even in the plains.

Look at the heights and the bridges, and you can realize that such a road is not feasible to be flat

1 Like

Let’s see what Eric thinks, being a professional in the field.
Hi @eric-s, if you have time, can you please come up with an assessment and some advices?

1 Like

You are right. It’s not flat. It follows the terrain somehow. I was going to bring the bridges down so they touch the terrain. But I thought I cannot use the dxf file I have of the road because it is always straight and does not match with the dxf design of bridges that show the correct slope.

You could do like this:

This way you can match each end of the bridge with the road. And of course to straighten the road in some areas so as not to have so many ups and downs, to be smoother.

Thanks @mihai.s for your detailed responses here. To me this is a problem that needs a bit more rethinking from the very beginning. Consider what we’re working and how they relate to one another:

  • A. The bridge model. Easy to import and align as @mihai.s showed earlier and was the original request for this post.
  • B. The existing terrain. Which right now has a road stamped through it that looks like a raised viaduct which we agree can’t and won’t be built like that.
  • C. The horizontal road alignment. Which was stamped over the terrain and is now causing some problems of its own.

What’s missing is the vertical road profile or road grading plan for the proposed road. We can’t go any further without knowing where the road will be ‘cut’ into the landscape or where it would be ‘filled’. We need spots or contour grades for that.

From the previous conversation it seems like if that information were available, we’d already have it. So a less accurate, but faster way to do it is to use a road/grading extensions like InstantRoad.. It has an option for building a road on an existing slope from a center line. This way the road follows the terrain but stays ‘flat’.


Thanks @eric-s for the answer!

I should have told you that in a previous discussion

I had already shown him how to create that flat road that would follow the terrain, like the InstantRoad plugin does while starting from the centerline. In addition, I showed him how to remodel his road so that he can texture it correctly (making quads, a plus compared to how the plugin creates the road).

The problem is that his boss thinks

that if the road follows the shape of the terrain, it has too many descents and ascents and he wanted it flatter, but the way the terrain looks, it should look like that.

This issue can be improved (solved) manually by moving the vertices vertically (animated Gif above) with the Move tool and flattening the road on certain shorter sections.

But the plugin you recommended automatically creates it, with the help of that setting: ‘Flatten vertical curves smaller than…’.

Thanks again, Eric!

Thanks to both of you @eric-s and @mihai.s.
You are right, the problem started to be one thing at the beginning but as I went further I faced more problems.
We do not have a vertical road profile for all length of the road. I just have the elevation values (ASPHALT) of the bridges starting and ending point and the spans. As an example, this is all I have for each bridge:

The pink line draw on on the bridge shows the asphalt quote and the values in the profile written in pink are corresponding to that.
Yesterday, I tried to use these limited elevation values to build a road manually over them and then adjust the terrain to that using smoove tool. But still the cut and fill will not be shown. This is what I obtained:

drawing road.skp (7.9 MB)
I see that this extension needs a subscription and it seems a very good tool. If I apply this method, will I be able to place the bridges under the road it will construct? Seems I need to delete the terrain under it. Did I understand well? Will it work in this case?
Thanks again to both.

Thanks dear @mihai.s.
I think I solved it with your help.

1 Like