Sweep in use with 3D Terrain

[Hulston1982]

I am trying to create a sweep that can run along the surface of a Toposurface and was wondering if anyone knows how this can be done effectively.

I have created a profile of a rail track and have used a sweep along Level 0 to form the shape of the rails, but due to the site toposurface being an imported instance of a 3D survey the rails pass through the toposurface at points making it look wrong withing the render.

I know i could creat various work planes and create little sections of track on the varying planes that are at different heights, but feel this could take ages.

I have attached an image to show how the rails pass through the surface.

Any help would be appreciated.

Alex

[Scott Womack]

Revit cannot create a 3D path that a sweep can follow. This is what is required to follow non-flat topo. You either have to create a path in alot of little segments, or take it into 3DS Max, create the swwep, export the sweep, out and get it back into Revit.

[Hulston1982]

Thanks Scott for the help. I've never used 3DS Max and would mean taking time out of a colleagues schedule to do this for me. So i'll leave this option for now.

Since posting though i have come up with a work around to create what i wanted.

Here goes:

I used the stuctural tool as this has a parameter within it that allows you to raise/lower each end of the beam as required. I chose a rectangular concrete beam for my instance as it looked a simple solution. Once loaded into the project i edited the family of this beam and imported a profile i had created of the track rail. Without having to change any parameters or losing any, it loaded in without warning and has worked. I saved this as it's own family and loaded into the project. I am unable to draw the beam/rail as a curve as the track would be but can now create a faceted type of curve raising and lowering each end of the beam/rail to suit the terrain.

This is not an ideal work around. Will post up an image when i have completed the track to show the result i gain. Seems to be working for now.

[AP23]

For this type of work, you are better off using the railing tool. Although the railing tool doens't follow the curves of a site, it does works as a sweep and is a much more flexible.

[benmay]

I would also suggest using the railing tool, its still not straight forward but with a little work it will acheive what you require

Another addition to that is you can use a ramp with a railing constrained to it, that way you can also build the track base at the same time (if required)

There are a few threads on AUGI about this if you need more info.

[tomnewsom]

Personally, I would cheat and Grade the topo so the rails can follow flat slopes
(this is what they should be doing anyway, right?)

[Hulston1982]

All,

Thanks for the replies.

I can see how the railing tool would work well here. Maybe in the future i will use this instead. It would be difficult to raise or lower the railing as you go along thoug as you keep on having to go in to edit the railing. (When not knowing each point of the topo)

With the beam i can edit each section in 3D view, and as this is how i've done most of the site now i think i'll stick with it.

Grading the Topo would work. Only this is an existing site. So if i graded the area of the track the track would be runing in the middle of a ditch. I did this first but it looked wrong. Although the site is very flat over all with only a metre and half or so difference from one side to the other with the odd mound. But i'd still need to grade the track to suit. The attached image shows how flat the site is but there is a difference of about 300mm just in this section of the track.


Thanks again all. It's fair to say we've a few various ways to acheive the goal.

I have attached a image of the track to show the result i got.
It's still not ideal in real life as i think the track would be a very bumpy ride, but gives the right effect.

[Andre Carvalho]

We have a project I'm working that has a huge rail yard sit on a slightly sloped land (changes between 5' to 8' to -2' from end to end).

I have created the rail tracks as railings and used sections of ramps to make them follow the land slopes. Ramps automatically come with two railings hosted to it. You can even have the left ramp railing as the left part of the track and the right ramp railing as the right side of the track. Put together they will form the rail track. The ramps then are on another workset (hidden). Using the spot elevation tool you can know exactly the start and end elevation points of your ramp.

See attached images (you can see the ramps bellow on one image)

Andre Carvalho