AutoCAD Civil 3D

[#1]

I have no experience with SAC and am looking for an "off-the-shelf" subassembly that might solve my problem.

I am working on a roadway which contains a superelevated slope for a small portion of the longitudinal distance. I am using AOR lane, shoulder extendall & daylight basin. My issue is that the DOT is requiring a 20' clear zone from edge of concrete to the ditch contained within the daylight basin. The said clear zone must be 6:1 slope. The basin is comprised of 3:1 slopes. 

My issue arises when I apply the superelevation to the shoulder, therefore decresing the daylight offset required of the shoulder. This decrease in offset reduces the clear zone. Is there anyway to make sure I maintain the required 20' while still being able to model subgrade correctly (i.e. apply super to shoulder). 

See attached to help carify my ramblings.

[#2]

Is this what you are looking for through your Super? 

[#3]

I think that you need to break this problem into two pieces.

LinkOffsetAndSlope attached to the shoulder will get you to the specified offset, no matter where you start it from.  Attach DaylightBasin to that to complete the assembly.

[#4]

That's what I used above with an Offset alignment for the edge of clear zone.

You could also use the Basic Transition SA holding grade, and show your contractor the topsoil depth, and do takeoffs on materials and earthwork.

[#5]

Thank you for your help. I think i have about got what I was looking for. 

I liked the idea of modeling the topsoil areas outside the gravel shoulder, so I chose to use the Basic Transition SA & target my 20' clear zone. My only remaining issue is the datum urface. FG models nicely, but the datum has a mind of its own. Any suggestions?

[#6]

Check your corridor in the section view editor, with the Datum surface turned on so that you can see what it looks like in section.  Usually problems like this are related to the surface being defined incorrectly.  Use Datum links with the Breakline option turned on, and the Overhang option set to bottom.

[#7 · Accepted solution]

Here's my Datum surface before and after Overhang Correction:

[#8]

Thank you for the help.

The overhang adjustment cleaned everything up nicely.

I appreciate all of the input.