earthwork quantities excep at bridge?

[Anonymous]

there's some old posts on this topic but thought I'd check in for latest

using C3D 2011

how to except out earthwork vic bridge?

thx,

[neilyj666]

new corridor regions before, at and after the bridge. apply null assembly at the bridge

[Anonymous]

thanks,

by "null" assembly, you just mean use no assembly at all?  in other words, just leave an unassigned gap in the corridor definition stationing?

[neilyj666]

yes create an assembly with no subs and use that

[Anonymous]

yeah, good, thanks! I'm also going to try it with an assembly with no daylight links and see what I get

[sboon]

This method may not work as expected.  Keep in mind that end area volume calculations make no consideration for what is happening between the sample line stations.  If you have a sample line at one end of the bridge and another one at the other end there will be a volume calculated between them, even though the surface does not exist in that gap.  The secondary  problem you will run into is that the TIN for your corridor surface will fill in the gaps between regions unless you use hide boundaries to enforce the breaks in the surface.

Steve
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[Anonymous]

much obliged,

then what strategy would you use to except out a bridge area instead?

how do you hide boundaries?

[fcernst · Accepted solution]

Civil 3d has already provided functionality for non-contiguous Material calculations such as the bridge gap scenario, and pockets of Materials.

The correct procedure to do this is to Gaps when you compute your Material Volumes:

[Anonymous]

that works great, the trick is to have sample lines set at the begin and end of the exception area

thank you

[sboon]

There are a couple of options for this issue

The corridor used for this road surface includes an assembly across the bridge with two horizontal links 1mm wide.  Those links have Top link codes and Daylight point codes so that the corridor surface is continuous across the bridge and its boundary is dynamic. 

In the volume table the last full section at the north abutment is at 27+63.10  There is another sample line at 27+63.30 where there is no fill and very little volume.  Across the span there is negligible volume accumulated until you get to the south abutment at 28+42.75

In this version I've left a gap between corridor regions.  The surface has been allowed to interpolate across the bridge.  I've deleted the sample lines between the abutments and applied a gap to the Material volume calculations as Fred suggested earlier.  This method simplifies the process of doing the calcs and provides a more accurate result but the interpolated surface across the bridge can be an issue if you want to display finished contours or sections.  The placement of the sample lines at the abutments and the gap stations are not dynamic so you need to update if the corridor changes.

Steve
Please use the Accept as Solution or Kudo buttons when appropriate

[Anonymous]

thanks very much, very useful example!  much obliged