Bridge Corridor Build Problems

[ph17il]

I have a corridor with a bridge in the middle of it.  I'm trying to compute materials of the embankment over the whole alignment.  I've applied my assemblies with daylights to the sections on either end and a different assembly for the bridge section.  I can't get the corridor to build correctly at the bridge section.  I want it to stop computing materials for this section and not fill between the road and the tin surface.  I've tried a number of different assemblies and corridor options, but can't get it to build correctly.  How do I get my corridor to build correctly without having to manually cut out portions of either the tin surface or the corridor surfaces?

Thanks,

Phil

[Anonymous]

Have you tried using a Null assembly in the bridge section?  Basically this is an assembly with nothing attached to it. 

[ph17il]

Ya I've tried that, the problem is that the corridor is connecting the daylights of the assemblies on either side and the computed materials include this information.

[sboon]

Which version are you using.  There are a couple of solutions for this problem but at least one of them is version dependant.

[ph17il]

We're using the 2011 version

[sboon · Accepted solution]

Option 1 - not sure if this works in 2011, but in 2012 you can add a gap within your material quantitiy calcs.  This method will give an accurate volume but still leaves you with surface contours and/or corridor feature lines running across the bridge span.

Option 2 - A variation on the null assembly posted earlier.  The two LinkOffsetOnSurface subs have very small offset values, point codes set to Daylight, no link codes and the links are omitted.  The LinkToMarkedPoint sub has link codes of Top or Datum, whichever is appropriate.  The idea is to have the corridor design surface run across the bridge as a very thin strip following the EG surface so that there is almost no volume to be calculated.

[ph17il]

Thanks Steve!  The LinkkOffsetOnSurface is the best solution I've tried.  Thanks for the help!