Modeling Gas Network - Constant Cover Pipe Rules

[quinnp]

I'm attempting to model a gas network using the pipe tools (Civil 3D 2011). The problems I'm having:

1) The pipes are coming in at all depths (mostly too deep), rather than at the constant 3' cover I would like.

2) Pipes all have zero slope and "stairstep" at null structures, instead of sloping with the surface.

My pipe rule set is:

Cover only, min/max 3'

Match pipe-to-pipe, inv 0'

I tried adding a slope rule, it dropped pipes lower.

For structure rules, I have tried both 0' drop across structure, and no rules (hoping pipe match would take over). All are null structures.

I do have the surface referenced, and it is being recognized (structure rims insert at grade).

Anyone have any solution ideas?

[wfberry]

Draw pipe at surface grade, when finished drop 3' (or 3' plus pipe diameter).

Bill

[C3D_User]

Don't even bother with pipe Networks. It's to much of a pain and not to mention a lot of overhead in the drawing. Create a new Profile Style and call it GAS.  Create a suite of Profile Label Styles for Pressure Pipe situations (Profile Label Sets).  I also do this with Water Mains. The best part is they are all dynamic, and a lot faster than Pipe Networks. I have tried some of the fancy new Pipe Network Structures and Pipes.  The problem with those are the way they look in Profile which is awful.

Regards, K

[Neilw_05]

There have been several posts about profiling water lines at a fixed depth from ground. Gas and other "dry utilities" can be handled similarly. Here is a recent post on the methods others have recommended.

http://forums.autodesk.com/t5/AutoCAD-Civil-3D/Feature-line-created-from-polyline-offset-from-alignm...

[annw2]

Hi:

That is my post from my first ever gas pipeline project.

If the goal is not modeling a lot of the pipes themselves, but mostly to show a gas line parralel to an existing or proposed profile, the corridor method from the post mentioned works the best.

Here is a summary and what I found out today.

Have alignment.

Create profile either from eg or design for the pipe to reference

Create assembly

  Vertical link down to top of pipe = desired depth of cover.

     Adjust subassembly property to omit link from model

  Add basic lanes left and right approxmately 1 ft wider than trench with pavement thickness = to diameter of pipe desired. 0% slope

Create simpe corridor from 3 above items.  Save drawing - Very important at this step.

Right click corridor to adjust beginning and ending stations - 50-50 probability of crash.  Will work the next time (?)

 Adjust frequency of sections to about 20' or what needed for pipes

  click off the sections at profile points if using eg.

  click off the super elevation option or anything else that looks problematical.

accept and save.

Trace along alignment and look for sections that cross each other - break corridor into segments with gaps where the section crosses occur.

Add cross sections at PI's where needed when the corridor necks down to nothing. - Accept and save

Create a top surface and use the automatic boundary feature for the top.

Check top surface - I was getting an 80 section at the 2.4 mile mark that shot down to 0 - No idea why.  I just created a gap in the corridor and let the model interprolate between.  Luckily it was a flat area.

Create a second surface from the datum and the boundary from the subbase.

Look for any other odd points.

Create a profile from each surface

Add profiles to profile view using a profile style to reflect your proposed pipe drafting standards - No labels

Create profile Label line style for "Proposed X" gas main"  Add label only between stations where you want it on each profile view.

I did this is a separate drawing then created data shortcuts of the profiles to DREF into each of the plan and profile drawings created for production plotting.

Hope this helps.  It took awhile for the concept to sink in for me

I haven't gotten to manual adjustments for obstructions yet.

[civ_engineer]

Did you ever get the pipe rule to do what you wanted?  Currently, I'm draping a feature on the existing surface, lowering the elevations and adding that to a network.  It seems like Autodesk would have a better method by now.

Civil 3D 2012, SP2

Windows 64 bit

[Neilw_05]

The "better method" is now the pressure pipe tool. It was just introduced in C3D 2013.

[civ_engineer]

Thanks.

I haven't made the transition to 2013 yet.  It tends to crash my project more that 2012 currenty does.

[BrianHailey]

http://civil3dplus.wordpress.com/2011/07/26/water-line-best-practices/

It's for water lines but should work well for any pressure system. I created this video to assist people that purchased our pipe network catalog so some of the instructions are specific for that but overall, it will help anyone doing pressure systems using the Pipe Network tools in Civil 3D.