Creating an Interference Check

Interference checks came around in Civil 3D 2007 and they are still alive in almost identical form in Civil 3D 2008.  I find that they are quite underused by my clients (ok, and me too) but they are really pretty easy to setup and very powerful.

You might be interested in finding the true physical collisions between pipes and structures from two different networks, or perhaps you need to make sure that your sanitary network and your water network always remain 3′ away from each other in any direction. 

Click more to find out how to set one up.

To access the command go to Pipes>Create Interference Check.

1. Choose any part from your first network, then any part from the network you would like to compare it to.

2. Establish your criteria.  Leaving the 3D criteria box unchecked will find actually collisions between pipes only.  Specifying 3D criteria will wrap your parts in an imaginary fluffy cloud in all directions.  For example, If I specify a distance of 3′, my parts will be wrapped in a cloud that is 3′ thick, and if that cloud touches a part in the other network, an interference is noted.

3. Run your check and read the dialog box that shows you how many interferences were found.

4. Look in your drawing for the interference markers.  If you drawing is big and there were only a few found, go into the Pipe Network tree of Prospector and drill under Interference Checks.  In the preview pane, you can choose on an interference instance, right click and do a “zoom to”. 

You can also check it out in 3D.

5. If you redesign your network to eliminate these interferences, you can run the check again by right clicking on the Interference Check entry in Prospector.


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