I know this question has been addressed here before, but it has been a while since the last post. It involves getting a curb and gutter subassembly to transition froma "catch" type curb (water flows from the road towards gutter flowline), to a "spill" type curb (water flows away from the gutter flowline towards the road centerline). Examples would be in superelevations or around some curb returns.
I cannot for the life of me figure this out. Any help appreciated.
Many thanks.
C3D 2014
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All of the OOTB subassemblies require that the gutter has a positive depth so I don't see how you could use them. You would probably have to create your own spill curb using a multilink sub or the SAC.
We had a similar debate years ago about modeling the gutter slope to follow the superelevation until someone pointed out that the slipforming machines used to construct curbs cannot build this. The contractor has to stop and switch to a different shoe when the gutter slope changes from positive to negative, and then likely do a bit of hand-forming to clean up the transition. You might be better with two subs and separate regions where you want spill curbing.
Steve
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All of the UrbanCurbGutter subassemblies have a Gutter Slope Method property. Set this to Outside Lane Super and the gutter slope will match the outside lane slope. This transitions the curb from catch to spill as the road becomes superelevated. Look at the subassembly's help document for more information.
You're right David. I've been using the older versions of these subs for so long that I forgot they had been changed.
Steve
Please use the Accept as Solution or Kudo buttons when appropriate
I always set the Gutter Slope Method to Outside Lane Super, and it never, ever does anything but remain a catch curb. This was why I asked the question, because this method seems intuitively correct, but fails in the real world. (At least in my experience it fails.)
I just did a quick test of this in Civil 3D 2013 with the UrbanCurbGutterGeneral subassembly. I applied a 12% superelevation rate to the outside lane. This is how the subassembly reacted:
As you can see in the image, the gutter pan slope matches the pavement slope.
This only works with superelevation applied to the alignment. It does not read the grade from the adjacent lane subassembly when using target profiles to control the edge of pavement elevation.
Ahhh... now we're getting somewhere! I need to apply superelevation to the alignment to get it to work properly.
Does that mean it is not feasible to use it on curb returns?
If your curb returns are being modeled with separate baseline alignments, you should be able to add superelevation to them as well.
We call it a Reverse Pitch Curb and Gutter...
I think David mean the "Gutter Slope Method" default value is "Outside Lane Slope" which can be changed to "Inside Lane Slope", "Fixed", or "Use Depth". Obviously the *Lane Slope choices use the slope of the pavement, while the "Fixed" uses the value you enter in the "Gutter Slope" box and "Depth" is the variables you provide further down.
I set my Urban curb & gutter sub-assemblies to "Fixed" because when pouring a monolithic C&G or S/W, C&G in real life the machine's internal form is the same regardless of the cross-slope. David is correct, is some places the transition between Std and Rev. Pitch C&G has to be done by hand.
I provide a gap between the regions using the different sub-assemblies and let C3D connect the dots. Needless to say, my transition never happens at a point I'm providing a cross-section.