Cut Bench Help

[Anonymous]

I currently have a site where I have cut a roadway along a steep slope. My roadway is at about 16% and my cut bank is at a 2:1. My client wants to add a few cut benches into the cut bank at certain elevations along the way (say 2 cut benches, each 5 feet wide). I can't seem to fingure out how to get my corridor assembly/subassembly to cut to an elevation at a certain slope and then to another elevation at a certain slope and then daylight at a certain slope. Any thoughts?

[Anonymous]

I'm guessing that you've already looked at the 'DaylightBench' subassembly and you've noted that although it does create benches, it creates them at a specified vertical change in elevation rather than to a given elevation. This would make your benches follow the same longitudinal slope as the roadway, and thus, not at a flat consitent elevation along the slope.

[Anonymous]

I had seen that subassembly and noted the same things you did, however, I am looking for flat benches. Thanks for the suggestion though.

[Anonymous]

Hypothetically, you could reprogram that subassembly pretty simply.

Or what about using feature lines? Take the corridor to the first step, then
export a feature line and grade it to the desired elevation. You'd have to
repeat the process if/when the corridor changes, but that's pretty
straightforward.

Just a thought...

--
James Wedding, P.E.
Technology Manager &
Associate
Jones & Boyd, Inc.
Dallas, TX
XP/2 on P4-3.4/1G
LDT 2006 & C3D2006/SP2
www.jones-boyd.com
www.ee2inc.com

[Anonymous]

Could you create additional asseblies with the subassemblies pointing to a profile for the bench elevation? The coordidor would get ugly in a hurry with multiple regions, but I think you could do what you are talking about with some of the smaller, less complex sub-assemblies combined to the overall desired product.

David

[Anonymous]

That's an idea I hadn't considered...I could see that getting pretty messy pretty quickly but if I was careful it could work. Thanks for the help.

[Anonymous]

I don't think this can be accomplished cleanly but here's something.

There is a "LinkSlopetoElevation" subassembly that sounds like it might do some of what you need. Assemble it a couple of times with another assembly that makes the flat benches and then a daylight link at the end. Each slope elevation link will have its own elevation. I'm hoping this assembly will kinda collapse on itself as it rises up through the specified elevations but I'm very uncertain on how it will react to various situations. It may require two assemblies at different ranges. One for a single step and another for a double step.

[Anonymous]

New info:

It will require a new assembly as the roadway reaches the target elevation of the slope elevation link, other wise the slope will go negative.

I think you should be able to leave some small gaps (5' ?) in between the ranges for the assemblies in the corridor which will allow for a smoother transition from one to another.

[Anonymous]

Any progress on this. We really need a subassebly that will do this.

I have never seen a road where the longitudinal slope on a bench follows the slope of the road profile, it is always level.

Any neat, clean suggestions. We chose to use 12D on some projects because of this.

Regards

[sboon]

Two solutions.  Use Subassembly composer to build one, or create an assembly using generic links and other OOTB subs to do it.

Steve
Please use the Accept as Solution or Kudo buttons when appropriate

[Anonymous]

Hi Steve

Before I go launching into subassembly composer, and I don't want to sound rude, but do you know it is possible to create a benching subassembly that produces benches with horizontal longitudinal slope (or some other slope) no matter what the profile of the road does, using the one assembly for the lenght of the cut batter? Have you done it or seen it done?

With the second approach you suggest with generic links and other OOTB subs, is it possible to avoid the problems mentioned earlier in this thread, such as having change subassembly or elevation target each time a bench level is reached?

Thanks for you help.

[sboon]

That's the problem with adding to a thread as old as this one.  The original solutions were posted before the newer Conditional subassemblies were added to the software.  It would be relatively simple to build an assembly that starts with a LinkSlopeToElevation, builds a bench then tests to see if there is enough room to build another cut slope.  If there is then it would repeat the process, otherwise it would daylight to the surface. 

I haven't done it with the subassembly composer but I have built an assembly from generic links that could handle up to 14 benches.  If that's possible then it definitely could be done in SAC.

Steve
Please use the Accept as Solution or Kudo buttons when appropriate

[Anonymous]

I hear what you are saying Steve, though I could not find another thread on this topic and I prefer not to run parallel threads.

I see how it would work once past the LinkSlopeToElevation. But with the LinkSlopeToElevation subassembly, if you set a target elevation, how does it handle being above that elevation or way below it?

Do you create a LinkSlopeToElevation subassembly for each elevation you want a bench at throughout the site (elevation range of 200m and benches at 8m intervals = 25 subassemblies), with a condition that says something like if in cut but the slope to elevation is down then skip to the next LinkSlopeToElevation subassembly.

Am I on the right track or is it easier than that?

[sboon]

You've basically got the right idea.  What version are you trying to do this in?

Steve
Please use the Accept as Solution or Kudo buttons when appropriate

[Anonymous]

2015. Thanks Steve. I'll give it a go.

[sboon]

Take a look at this example.  The first half of the profile is fairly flat, so the benches are simple but the rest is quite steep.  I had to introduce a series of steps into the profiles that control the bench elevations so that they would always be higher than the centerline.

Steve
Please use the Accept as Solution or Kudo buttons when appropriate

[Anonymous]

Thanks Steve. Good to see what you had done with the profiles. I was trying to do it without any additional profiles and I couldn't stop it grading down to my LinkSlopeToElevation below the road and only use the ones above road level.

The profiles make the use of LinkSlopeToElevation redundant as it is over riden by the profile targets. What you have come up with is an improvement, the benches are horizontal but still don't look like what we build in real life. The benches keep steeping down, how is an excavator supposed to go along that.

I will put a support request into Autodesk, it's a pretty standard thing to have horizontal benching along road corridors.

Thanks for your input Steve.

[Anonymous]

I had a bit more of a play around and used a variation on Steves method (see attached drawing).

Steve used one assembly but controlled things with multiple profiles for elevation targets.

I also used one assembly but instead of using profiles I created a series of feature lines at all the bench elevations, just as single segment lines that run the length of the site and then set multiple regions each targeting a different featureline for elevation (this also avoids and vertical step in the batter). I also added width targets to taper the bench width where is meets road level so there are no horizontal steps in the batters.

So not too difficult once your head is around it, but whether you use profiles or regions it would still be time conuming to adjust the profiles or regions it the alignment/profile is changed.

[Civil3DReminders]

I made this a while ago, haven't updated it recently to the new versions since I haven't had to use it.

http://blog.civil3dreminders.com/2010/12/custom-bench-subassembly-updated.html