I have a rail assembly and i want to slope down 2:1 to a ditch 2m wide then slope up 2:1 to daylight to OG. the ditch does not have to be 2m wide (varies) depending if it daylights inside the right of way. also i want the botom of down slope to foloow a profile i created to accomodate existing culverts.
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Thank you for the reply. I still am having trouble my back slope can be variable but would like to maintain 2:1 slope. the ditch can vary max 2m to vi ditch and the ditch is profile dependent. my constraint is i need my backslope to remain inside the right of way. Please find the PDF attached to better explain of a cross section.
You may need to use the Link Slope Between Points, this one can be a little tricky your first time. This will hold the slope of the backslope and narrow the ditch bottom if you do it correctly.
Daylight Max Offset. You'll need to define the property line as an alignment or polyline and use it as a target for the maximum offset. This will steepen the backslope if required to fit inside the specified offset.
This sounds like an engineering optimization problem.
There is another parameter here to consider.. the hydraulic capacity of the ditch (with freeboard).
The V-ditch has to be deeper for a given required capacity than a ditch section with a 2m wide ditch bottom. The 2m bottom width ditch profile can be flatter with a subsequent shorter vertical daylight catch differential, for a given required capacity.
If capacity is not an issue, then V-ditch is going to win every time for your best chance at catching at 2:1 within ROW for a given constant profile.
it seems like you're saying you have a profile you want to stick with...
I think Matt has the right idea, but you could add conditional tests to refine it. The foreslope down to the inside edge of the ditch is fixed by the profile. From there the question is whether or not the 2m wide ditch fits in the R/W. If you used LinkWidthAndSlope and LinkSlopeToSurface with the omit link option turned on then you could use a conditional test to determine if you were inside or outside of the R/W line. If you're inside then use LinkSlopeAndVerticalDeflection plus LinkWidthAndSlope to move back to the original foreslope point before applying a daylight subassembly to finish. If you're outside of the R/W then use LinkOffsetOnSurface to set a MarkedPoint on the R/W line before moving back to the original ditch foreslope point. Use LinkSlopesBetweenPoints to finish.
Please use the Accept as Solution or Kudo buttons when appropriate
LinkSlopeVerticalDeflection doesn't give the horizontal targeting capability needed to tie into existing culverts.
Using LinkwidthAndSlope for the foreslope link does.
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