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swharton
2011-01-26, 06:36 PM
I am about to start a project, that is going to require roadside ditches where the elevation varies dramatically. Is there any way to build a corridor that builds a ditch, that has a 4:1 SS, 2' BW, and is at least 1.5' deep, but no more than 4'? I have already done one project like it, but did it the old fashioned way using pencil and paper, but want to try and streamline the next section and have C3D do it for me. Anyone have any suggestion? Thanks!

tonycarcamo
2011-04-26, 03:17 AM
you can create profiles for your CL of your ditch to target or you can create featurelines to target horizontally and vertically. You can use generic Linkwidthandslope subasembly

tony
senior design tech
www.tonyscivil3dworld.blogspot.com

indydrafter
2011-06-06, 12:48 AM
Once you've done what Tony said, you can then set the width and profile targeting within your Corridor parameters for the subassembly in that Corridor Region.

WScottAllenPE
2011-06-13, 12:32 PM
I know that the initial post is month old, but I have a suggestion that may help other users with similar questions.

I completely agree with what the other posters said, but the question is how can you know at what elevations and slopes to create a ditch to meet your limitations of min 1.5' and max 4' deep? Trial and error? Fortunately, there is a better way to get your upper and lower limits.

On your assembly, create a "LinkSlopeAndVerticalDeflection" from the point of your top of ditch. Go UP by your minimum depth at your side slope. Then "LinkWidthAndSlope" at 0% for your bottom width, then "LinkSlopeToSurface" at your backslope. This will give you your tie in point. Then create the same three subassemblies, but DOWN and back toward the centerline. Essentially, you have created a polygon, where your bottom is always a ditch that is your minimum depth.

By naming a point on the bottom, you can create a feature line or a polyline of the bottom profile. You can then project it to your profile.

By doing this to your min and max depths, you have drawn on your profile view two lines as boundaries between which you draw in your final ditch profile, to which you can then target your bottom of dich.

Scott