Modelling corridors with hairpin bends

[neilyj666]

I'm modeling a hydro scheme access track about 4m wide that meanders down a steep hillside at 1:8 with a couple of hairpin bends where the gradient is 1:20,    what is the best way to model this?I have got polylines to define the hairpin and also offset alignments but I need to ensure that the outside edge of the hairpin at entry is used as a level target for the inside edge on exit for the length of the hairpin

Thanks

[MikeEvansUK]

Neil have you got any pictures to assist in what you mean.
What do you mean by level target on exit?

[Neilw_05]

I think you are saying you want the outside edge of the road to match EG when entering the turn and on also on exit where it becomes the inside edge. You also want the slope between those 2 ends to be 1:20. If I have this right then what I would do is get Terry Dotson's tool for finding an alignment along a terrain at a given slope and use that as a guide to layout your edge of road alignment. Then layout a profile that hits those key points.

[sboon]

I read a little differently.  It sounds like he wants to ensure that the inside edge of the road stays at reasonably the same elevation around the curve, as the centerline profile drops at 5%.

BTW - is it 4m wide all the way, or are there widenings through the curves?

Steve
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