Overlay and Widening problem

[jwayand]

I am having a problem with an overlay and widening C3D 2012 project. The subassembly I have chosen is processing with the corridor datum surface cutting into the existing road surface, as would happen with a “milling” section (which I don’t want), I need it to overlay onto the existing surface only, with a nominal minimum thickness of 4” . I think this subassembly is drawing the datum surface from the datum point of the widening on one side to the datum point of the widening on the other side, not sampling the "bottom" of the overlay surface. See attached screen shot. Also attached are screen shots for some of the subassembly and corridor parameters for my current settings. I am using the “overlaywidenmatchslope1” and “basicsideslopecutditch” subassemblies.

I have tried changing the sample point offsets and the insert point offsets without fixing this problem. I have not added any additional alignments for saw-cutting yet as I am trying to keep it simple until I get the assembly to process correctly with a fixed width.

I looked at trying the “overlaywidenmatchslope2” subassembly, but it is for non-crowned roads and would not work for this project. Are some of my parameters wrong? Is there another subassembly that I should be using? I could use some suggestions for possible cures and would appreciate it. Thanks, John

[sboon]

I've run into the same problem.  The only thing I could do was to create two datum surfaces with separate boundaries.

[jwayand]

SBoon,

Thanks for the reply, I am just beginning in C3D, so I am glad to hear someone else has had the same problem.  I was assuming that I was doing something wrong, so I submitted my drawing to Autodesk Tech Support for help- they could not find anything wrong with my subassemblies, settings, etc. and so they have sent the problem to the Autodesk Development Team for troubleshooting as they think there may be a problem with the subassembly.

So while I am waiting for a reply, I am trying different fixes - I may change to the overlay & milling subassembly, temporarily, just to be able to continue work, then revert back to the overlay only template when a solution is found.

Did you set up the two datum surfaces in the Corridor settings?  Do your cross-sections turn out correctly?

Thank for the suggestion,

John

[Cadguru42]

Almost all of my projects are overlay and widening projects at intersections, yet I cannot ever get the subassemblies that are supposed to be made for that type of project to work the way we need them.  I usually end up using the basic lane transitition as the overlay subassembly and then do a regular lane for the widening portion.  We just want the overlay to be 1.25" above the existing surface, so I make profiles that match the existing CL and edge of pavements and use that as targets for the overlay.  I know there are dips and such in between the centerline and edge of pavement, but noone cares about that here.  They just want the elevation of the back of curb for the extended portion, and by doing what I mentioned I get that.  

I just feel that Autodesk has left the road rehabilitation tools alone without ever thinking how someone really uses them.  An overlay subassembly should be very simple and not require most of the parameters that the current ones require.

[sboon]

They're probably not going to find anything wrong since the sub behaves "as advertised".  The real problem stems from the fact that the programmers didn't really consider the possibility of a corridor which works on both sides of an existing roadway but leaves a space in the middle where nothing happens.

[machadt · Accepted solution]

Hi John,

The issue that you are experiencing is a known issue that our Development Team is looking into.

I apologize for the inconvenience and thank you for your patience and understanding.

[jwayand]

Hi,

I'm glad to hear the team is working on this problem: since its been awhile, any idea how long it might be until they reslolve it?

Thanks,

John

[sboon]

I actually ran into this problem again on a recent project and found a solution that seems to work.  What I did was to add a StrippiingPavement sub at the inside edge of the widening, with a depth of 0.0001  This sub adds links that follow the existing surface.  I then added these "stripping" links to my Datum and Top surfaces, so that they were contiguous all the way from the widening on one side across the area of no work in the middle to the widening on the other side.

[apweng]

Hello,

Yes this is an issue with OverlayWidenMatchSlope.

Why don't you consider an iterative process to get around this?

The 1st pass with OWMS could be used to generate feature lines or alignments/profiles at offset locations.

Then create a 2nd assembly using generic links for the overlay part and LaneOutsideSuper for the full depth reconstruction part.  You could then target the feature lines (or alignments/profile) you created from the "1st pass" corridor with OWMS.

With the 2nd assembly assign unique link codes (ie RESURF) to the generic links used to model the overlay component, create a RESURF surface and calculate overlay quantities between RESURF and EG.

This "dual pass" approach to road reconstruction can be useful and not overly laborious.

Lot's of different ways to approach this design challenge.

Hope this and the other suggestions help you along your way!

Regards,

Andrew

[LeafRiders]

Not sure exactly what approach to take. Regardless, there should be an easier method / approach based on the subassembly composer to derive what we're trying to get here. Every road needs to be stripped down prior to construction. These options are labouring especially depending on the complexity of the road. Maybe for C3D 2015 us roads guys can get some practical Autodesk development on the roads side of things. There is another piece of software in town that's focused on roads and is making a push. Maybe C3D developers can get back to practical and bipass the fluff for a season or 2.

[jwayand]

LeafRider,

Thanks for reply. I did actually discover a solution and should have posted it for anyone interested.  I studied the Help file for the "overlaywidenmatchslope1"  subassembly and realized the it includes an Overlay link (L2).  So I added a Link, Code type of "Overlay" to the Datum surface in my corridor (surfaces tab), so now I have both a Datum and an Overlay Link for the datum surface.  After updating the corridor and checking the section viewer, the error seems to be fixed.

-John

[LeafRiders]

Funny you say that, i've been trying to get the same SA (OverlayWidenMatchSlope1) to work as I need it to, but can't seem to generate a true stripping surface that matches the EG at say an offset of 75mm. Earth / topsoil stripping effect. I'll attach an image so you can see where I'm at with this.

I'm using basically 5:1 (-20%) as my slope and the OG surface as my datum surface for targets. I'd like the slope of the bottom of stripping to match the EG surface just 75mm lower.

Top target being my Edge of Shoulder (which is a survey figure or Feature Line), and the daylight of my finished ground. (which i created by create polyline from corridor, then turned that into a feature line).

It's close but not something I'd be 100% with on quantities. Thoughts anyone?

[sboon]

I'm confused - are you saying that you're using an Overlay sub to approximate a stripping surface?

Why not just use a Stripping subassembly?

[LeafRiders]

Enlighten me on how I get this Stripping SA to only to go from the Exisitng EOP to Daylight of the Design Surface.

[machadt]

Unfortunately once we escalate a case to our development team, they have to perform their own research as to what might be causing the problem as well as how to fix it.

Their schedule is regulated by service pack and new release timeframe.

I do apologize for any inconvenience that this may cause you.

[sboon]

Use a generic LinkWidthAndSlope to locate the inside edge of the stripping.  Note - you only have to locate it horizontally, don't worry about the elevation.  Attach a StrippingTopsoil sub to that - it will locate the surface elevation at your shoulder and cut outward until it reaches the specified width or a target polyline which you already have.

You can also use a ConditionalHorizontalTarget sub before the LinkWidthAndSlope to check whether or not the shoulder line exists at each section.  This allows you to control where stripping is applied - not at intersections or driveways for example.

If you want to get even more tricky then add another StrippingTopsoil at the centerline, with a depth of .0001  This will allow you to build a single stripping surface which follows EG, except for the areas where you intend to remove material.