Part Units (Millimeters/Meters)

[Anonymous]

I am wondering if anyone knows if the units in the 'parts creator, pipe networks can be changed to meters insetad of millimeters. I am working with some one who is trying to put XML files into XP SWMM and it seems as if XP SWMM requires units to be meters. Please let me know if you can confirm either way if this can be done.

Regards,

Chris

[Matt.Anderson]

Chris -

The LandXML specification should indicate a diameterUnit which Civil 3d respects. The workflow I might suggset is to take the pipe network into SSA and export to XPSWMM from within the Autodesk Storm and Sanitary Analysis program. (SSA)  While you are in SSA, why not perform the analysis there.

Not to avoid your original question, it is quite possible to edit the part builder library units, but that process is going to simply be quite labor intensive.

[Anonymous]

Hi Matt, sorry its not up to me to tell our water engineers which software to use SSA (at this stage). I think you are likely aware that its very hard to get people to use something they see a different and new for any number of reasons. For example, the software does not have same functionality or they may be affraid they will not be able to pick it up, the job demands on peoples time means that they do nort have time to swap. Whatever the excuse people make have or create not to use SSA I am in a position of it I can not get C3D to work with XP SWMM I may not be able to assist this office to make the change from 12d to C3D. So far everyone I have shown the software seems to like it so at least we have a goo start.

In respect to your option to default meters as the units and you please expand a little more. For example, 'The LandXML specification should indicate a diameterUnit', what do you mean here. I have looked at the XML file and elevations are in meters, so are pipes, but because C3D has units mm for pipes it shows and 375mm pipes at 375m.

If you can help me move forward with this then I feel we have take a good step forward I would really appreciate it.

Regards,

Chris

[Matt.Anderson]

Let me tackle this issue one by one.

• Editting the parts in the part catalog from mm to m will likely not solve the issue of exporting the file out to LandXML. Ie, there is not a method to specify which unit to export pipe diameters.  There will be a lot of text editting and testing, and part swapping to make this work. 

<Metric areaUnit="squareMeter" linearUnit="meter" volumeUnit="cubicMeter" temperatureUnit="celsius" pressureUnit="milliBars" diameterUnit="millimeter"

The pipe diameters in the XML file are 375 units.  The unit is mm since it is a diameter.

• XPSWMM should recognize the diameter units of the pipes if it is reading the LandXML file.  I am not sure if it does or not.  If it doesnt, replace 375 with 3.75 in the XML file.

• Use SSA to provide the data transfer mechanism.  Ie, if you EditinSSA, the SSA m odel will open with the pipe network translated.  From there, export to EPA SWMM or XPSWMM are both model options.

If you do not feel comfortable tell the engineers to use SSA for analysis, be sure they understand that it is there and is the mechanism to transfer data from the Civil 3D model out to SWMM.

[Anonymous]

Matt, I have to get on with chargeable work for now but will check out your posts at lunch. Just a note though we only run C3D 2011, as its a mainly 12d company at the moment and few people use C3D. I have asked with 2013 will be rolled out. Hopefully it will be soon.

Cheers,

Chris