Conencting seperate surfaces

[martin888888]

I created a grading and a surface for a pond that is abotu 30' away from a roaway that has a seperate surface.  What would be the best way to connect the two surfaces?  I need a uniform slope from the edge of pavement to the top of berm of the pond.

[Alfred.NESWADBA]

Hi,

>> What would be the best way to connect the two surfaces?

Create a new (empty) surface, then (within prospector) go to the details of this new surface ==> Definitions ==> Edits ==> Paste Surface .... and paste first your existing surface, then same again and paste the surface from the grading.

At the end you can set the orignal surfaces for existing ground and that for the grading to a style that does not display them, or freeze the layers of the surfaces and you only see the finalized version of your terrain.

- alfred -

[ericcollins6932]

I like Alfred's approach but I think he assumes you have an existing surface when it appears you are trying to connect two FG surfaces (?)

Same approach as Alfred - create a new surface, paste in your other two surfaces, and then edit and add tin lines and you will get a connecting surface between the two.

[MikeEvansUK]

If there's a gap in between the two surfaces adding lines is a long workaround.

To close the hole quickly, export each of the surface boundarys or a defining featureline / 3d polyline and add to the definition before or above the pasted surfaces.

[ericcollins6932]

Mike's solution would work too - it all depends on what you want. Do you want a simple planar surface between the road and pond or more detail?

Adding TIN lines "could" be a lot of work depending how many vertices there are. But you also have full control on how many you add if you go this way. On the other hand, if the pond only has a few vertices on the side of the road, addling TIN lines is a few seconds of work.

[martin888888]

Thanks for the responses guys.  The attachment might explain better what I am trying to do.

I have a pond surface and I have a roadway surface.  I want to grade in between each to get rid of excess cut.  What I am struggling with is how to model this and still maintain a catch point down the existing slope. 

[troma]

What is a 'catch point'?

I think your best bet is probably to do as advised above and then look at what you've got and see if it's good enough or not.  You can always add more data later, like a feature line in the middle somewhere giving a little more definition.

[martin888888]

A catch point is where your proposed surface hits your existing surface. 

I am finding its almost easier to explode your surfaces and draw in polylines

[troma]

So, sounds like you could either

1. Use a feature line and a grading group to grade at a certain slope until you hit your existing surface.

or

2. Create a proposed surface.  Then create a volume surface between exisitng and proposed.  Extract the 0 contour of the volume surface.  Create a surface called "existing retain"; paste in the existing surface and add the 0 contour you extraced as a boundary.  Create a new surface called "proposed with retained existing combined"; paste in the proposed surface and then paste in the "existing retain" surface.

[martin888888]

Thanks Again, another question.......If you have a fault line and in the grading you offset half of it at 3:1 slope and then the other half at 20:1.  Where the 3:1 and 20:1 sections meeting how do you make them interact with each other instead of the contours just deadending without transitioning?

[troma]

Not sure of the best way.

Maybe if you just leave a gap you will get the best result.  Stop the first grading a little short, and start the next one a bit late.  I think the surface will just triangulate across the gap, giving you a transition.  Then you can play with the size of the gap to get the best result.

[ericcollins6932]

If the offset featurelines are in the same site and you ensure the offsetting will pass each other, they will naturally intersect and clean up for you.