ORD - Intersecting Earthworks

Hi

I am trying to model the earthworks between an on/offslip and the mainline, however just past the diverge taper, the earthworks end conditions overlap.  I could create an end condition exception to remove the slope, but this will create a void between the two corridors, which wont be accounted for in the volume calculation.  In MX I would usually have the option of modelling this in two ways.

1 - Create a slope signature string between the two back of verge strings

2 - Use a 103/105 minor option to create a string at the intersection between the two slope.

Does anyone know what the equivalent Openroads workflow is.

Thanks

Stewart