AutoCAD Civil 3D Customization

[#1]

Already posted this in the general C3D forum with no success, hopefully someone here can lend a thought...

I'm wondering if anyone out there has used a non-AASHTO curve widening formula to calculate automatic curve widening for an alignment?  I'm trying to use our Agency curve widening formula which is a function of curve radius and  central angle.  

I'm not sure if it is even possible to use the central angle of the curve for calculating widening, or how one would go about using a non-AASHTO CW formula.  Does anyone have any thoughts here?

Attached is the curve widening formula that needs to be used.  L will be a constant here.

Thanks in advance

[#2]

Have a look into the file "_Autodesk Civi l 3D Roadway Design Standards.xsd" located here "C:\ProgramData\Autodesk\C3D 2013\enu\Data\Corridor Design Standards" for civil 3d 2013, (C:\ProgramData\Autodesk\C3D 2012\enu\Data\Corridor Design Standards for 2012) and the file " _Autodesk Civil 3D Imperial Roadway Design Standards.xml" located here C:\ProgramData\Autodesk\C3D 2013\enu\Data\Corridor Design Standards\Imperial.

In the second file you will find the section on widening methods which explains the variables available for use, and gives an example of widening by formula and also by table. It shows the "AASHTO Simple Formula" and "AASHTO Standard Formula"

I would make a copy of this file and edit the copy to create a new widening method (using a name you like) based on your formula.

The first file specifies how the standards file is constructed and what pieces are required or optional.

[#3]

This makes sense that one would want to make changes to this file to modify the curve widening formula.  However, I need to be using a formula based on different variable than are defined in the file.  Specifically I need to be using the Central Angle and Radius of the curve.  Radius is defined as an available variable, however central angle is not.  I'm not sure if it would even be possible to define a new variable by modifying this file.  Is this possible?  If so how would you want to go about it?

[#4]

I think this is a question to throw at autodesk.