Profile Design

[MPozzie]

When I change the grade in or grade out of a profile the PVI moves up or down in the same position. I have 2 tangents with the 1st one at +2% and the 2nd at -1% (the high point is at end of tangent 1 and importantly the end of tangent 2 is at a fixed elevation). Is there a way of changing the grade in of tangent 2 to -2% so that the station of the high point moves instead of it moving up or down? In my experience the grade out of tangent 1 changes when I do that and the high point stays in the same place. I want the grade out of tangent 1 to stay the same.

[rl_jackson]

I don't have a picture of what you're doing but if you're holding the end of tangent 2 at x elevation and want it to be 2% grade downstream (back) and then you want tangent 1 to be a 1% it sounds line you need to change the station and elevation of the PI to reflect the intersection of the 2 grades. The grade for the end of tangent 2 is the control

[Jeew-m]

Look at your case.

Two tangents with +2 and -1 gradients result in a crest curve.

But when you change +2 to -2 the resultant curve is a sag curve. There is no high point in the sag curve.

[MPozzie]

I thank you for your replies. I insert snips of the situation I am trying to describe which will hopefully be clearer.

Snip 1 - start of 1st tangent and end of 2nd tangent are fixed

Snip 2 - when I change the grade in of 2nd tangent it changes the grade of 1st tangent and high point is at the same chainage

Snip 3 - the result I want, tangent 1 must stay at the same grade but the high point must shift when the start of tangent one and the end of tangent 2 are fixed

[Jeew-m]

I wish you could do it using manual CAD lines.

Have a 2% line from the fixed start point.

Then have the same at the fixed endpoint.

Extend them until they join.

Then add the profile line along the CAD lines.

[jroot]

I assume you are making these changes in the Panorama box, right? (not grip editing or some other way)

[chriscowgill7373]

I have had the best luck in this situation using what @Jeew-m is suggesting in post #5