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Using negative cut slope

19 REPLIES 19
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Message 1 of 20
jhoff
7038 Views, 19 Replies

Using negative cut slope

I have a simple driveway corridor along a steep hillside.  For cut, I would like to have a negative slope away from the shoulder edge.  I have tried numerous approaches and all 'cut' reverts to positive.  I searched and found no clear answer.  It's such a short driveway, I can 'fake' it in, but I would like to calculate quantities.  What is the answer? Why is this so complicated? Thanks.

 

Using 2012 sp1, 64bit, windows 7

19 REPLIES 19
Message 2 of 20
sboon
in reply to: jhoff

In the programmers terminology "cut" is always upwards, and there is no such thing as a negative cut slope.

 

How are you building this slope - grading objects or corridor?

Steve
Expert Elite Alumnus
Message 3 of 20
jhoff
in reply to: sboon

I'm using a corridor. 

Message 4 of 20
sboon
in reply to: jhoff

There are several subassemblies that will allow you to force a downhill slope from the road shoulder to a specified distance or elevation, then back up to the ground surface.  A drawing or sketch showing what you already have and what you're trying to achieve would be helpful.

Steve
Expert Elite Alumnus
Message 5 of 20
sjg
Advisor
in reply to: jhoff

You could use the Generic LinkSlopetoSurface
Steve Goessling
Land Consultants
Civil3D 2015
Windows 7, 64 bit
Intel i7 2600 @ 3.40Ghz
16 GB RAM
Nvidia Quadro 600
Message 6 of 20
jhoff
in reply to: jhoff

Well, I tried that.  It will work if I specify only cut, but it won't display.  See attached.  I just need to specify a simple bench cut.  Suggestions?

Message 7 of 20
sjg
Advisor
in reply to: jhoff

Did you select the target in the corridor for that link? Did you change the link or point code name? If so, is your code set style set to display that link name?
Steve Goessling
Land Consultants
Civil3D 2015
Windows 7, 64 bit
Intel i7 2600 @ 3.40Ghz
16 GB RAM
Nvidia Quadro 600
Message 8 of 20
sboon
in reply to: sjg

LinkSlopeToSurface may not be the appropriate choice for this situation. If you want to enforce a downhill slope to a surface which is a cut situation then there is a workaround using the DaylightGeneral sub to do this.

 

DaylightGeneral builds a series of temporary links out to a test point, which is normally at the outside corner of a ditch.  If this point is in cut then it continues to build the rest of the ditch and daylight.  If any part of the temporary links are in cut, but the test point is in fill then it works backward along the links until it finds an intersection with the surface and daylights there.  For your scenario I would put the test point at the end of the first temporary link, and make that link at the correct slope but very long so that the test point would always end up in fill.

 

Steve
Expert Elite Alumnus
Message 9 of 20
apweng
in reply to: jhoff

Hello,

 

It may not be overly apparent - but if you use LinkSlopetoSurface and in Subassembly Properties, specify Fill Only, the Subassembly will project a "downward" slope, in a Cut condition.  

 

I've attached an image that shows something similar.  Note the Subassembly Properties (Fill Only) and how this parameter is interpreted in the Corridor Section Editor.

 

Hope this helps.

 

Andrew

 

Fill Only.png

Message 10 of 20
david.zavislan
in reply to: jhoff

The default daylight subassemblies have conditions that do not allow negative slope values.   Using Subassembly Composer you can create your own daylight subassembly that does not have any restrictions on slope value. 

 

Attached is an example subassembly that I use for these conditions.

David Zavislan, P.E. | Wood Rodgers, Inc.
Message 11 of 20
jhoff
in reply to: jhoff

That worked.  Thank you! 

Message 12 of 20
dtham
in reply to: david.zavislan

Hi David,

 

This is a very useful tip.

 

I am fairly new to Civil 3D.

I download the NV5SimpleSlopeAlowsNegative.pkt source file.

 

I imported the file to my tool Palettes.

Is this file replaced LinkSlopeToSurface?

 

I reconstructed my assembly.  I still couldn't get it to work.

 

Thanks

Message 13 of 20
david.zavislan
in reply to: dtham

This does not replace any stock subassemblies.  You import it into your tool palette and add it to your assembly like any of the other subassemblies. 

 

It only has parameters for side, cut slope, and fill slope.  The slope parameters will allow negative values.  This lets your model daylight up in fill situations, and down in cut.  You just need to make sure that the slope values are flatter than the target grade so that they will have a chance to catch.

David Zavislan, P.E. | Wood Rodgers, Inc.
Message 14 of 20
dtham
in reply to: david.zavislan

Thanks David.

Saw it YouTube, assembly composer. Pretty straight forward.
Message 15 of 20

I am curious if there are any version limitations with the "NV5SimpleSlopeAlowsNegative.pkt" that you created. This worked well for me in 2014 but will not work in 2011
Message 16 of 20
doni49
in reply to: ddachille10


@ddachille10 wrote:
I am curious if there are any version limitations with the "NV5SimpleSlopeAlowsNegative.pkt" that you created. This worked well for me in 2014 but will not work in 2011

Try downloading the pkt file again and then import the latest download directly into 2011.  Once a pkt file has been opened in any newer version 2014, it can't be used in previous versions.



Don Ireland
Engineering Design Technician




If a reply solves your issue, please remember to click on "Accept as Solution". This will help other users looking to solve a similar issue. Thank you.


Please do not send a PM asking for assistance. That's what the forums are for. This allows everyone to benefit from the question asked and the answers given.

Message 17 of 20
ddachille10
in reply to: doni49

I gave that a shot, but unfortunately I am still receiving the same error. "One or more subassembly .NET classes could not be found. Check Event Viewer for more information. Continue?". Any thoughts on that error message?

Message 18 of 20
doni49
in reply to: ddachille10

Oh yeah. You're talking about C3D 2011. That was the first version in which you could add a custom sub assembly (that's what the pkt file is). Sub assembly didn't come with C3D you had to download and install it.

So check to see if you have sub assembly composer 2011 installed. Install it if not.


Don Ireland
Engineering Design Technician




If a reply solves your issue, please remember to click on "Accept as Solution". This will help other users looking to solve a similar issue. Thank you.


Please do not send a PM asking for assistance. That's what the forums are for. This allows everyone to benefit from the question asked and the answers given.

Message 19 of 20
ddachille10
in reply to: doni49

Thank you very much doni49 ... installing the sub assembly composer 2011 was the answer
Message 20 of 20
mikeshick
in reply to: david.zavislan

Dave, Thanks for posting.  I came across your post, and tried your assembly.  My condition has a need for negative cuts but with varying slope conditions.  Sometimes a 2% cut clope will work, but in other cases I need a 2:1.  Could you offer any help on this?

 

Thanks!

Mike Shick
www.medesigns.us

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