AutoCAD Civil 3D - Stormwater

AutoCAD Civil 3D - Stormwater

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Registered: ‎10-03-2006
Post 1 of 3

SSA - Modeling Cross-Connections

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04-30-2012 08:49 AM

I am looking for advice on how to model storm sewer cross connections in SSA.  We have large trunk sewers that are inter-connected at a few locations.  Basically two large pipes coming together and two large pipes leaving.  In some cases, one of the pipes leaving is slightly higher than the other outlet pipe.  We tried modeling as a simple junction, but this does not seem to accurately split the flows.  Any advice would be appreciated.

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Post 2 of 3

Re: SSA - Modeling Cross-Connections

04-30-2012 12:58 PM in reply to: ThomasGlidewell

The program allows Flow Diversion Structures, limited to only two dischage outlets per structure (your situation).  Unfortunately that is the extent of my knowledge on this subject.





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Post 3 of 3

Re: SSA - Modeling Cross-Connections

06-21-2012 07:23 PM in reply to: ThomasGlidewell

did you ever find a solution to this topic? i would be interested to know how to model split flows in SSA, like i can model split flows in HEC-RAS for open channels.


i think Bill's suggestion is great and in the right direction, as the flow diversion tool allows two outlets. my initial thought was the "overflow" option in flow diversion, but that would not be a true split flow condition, as the excess flow will only divert to the secondary link when the primary is flowing full in that case. hopefully Matt or someone very knowledgeable in these topics can shed some light into this.


 *EDIT: i *think* that you may be able to model the manhole as a storage node, as that should allow multiple outlets. just a thought. i will have to test it tomorrow.

Avishek Chhibber, P.E., CFM
Civil 3D 2014 SP2, Win 7-64 bit
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