Cut and fill analysis

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Civil 3d surfaces can be used to calculate

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volumes of cut and fill between two surfaces.

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Generally, this is between a design surface

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and an existing ground surface.

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We can create a tin volume surface using the surface creation tools

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and set our base and comparison surfaces.

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However, we often need to assess multiple design services. At the same time.

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The volumes dashboard on the analyze ribbon tab

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allows us to do this.

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We will want to adjust our surfaces to optimize the amounts of cut and fill

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while still maintaining our design standards.

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We can edit the road profiles used in our corridor models

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and update the volume surfaces automatically.

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The start of sycamore heights is controlled

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by our intersection with Mcallister Boulevard.

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We will need to set this to rebuild whenever a design change is made.

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Select the intersection in Prospector,

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right, click and select update regions automatically

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choose, continue with update.

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When the warning is displayed,

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the intersection will be rebuilt.

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Next, select the Sycamore Heights Corridor in Prospector,

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right. Click on it

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and select rebuild. Automatic.

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Both the intersection and the corridor

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will now rebuild when they need to

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from the analyze ribbon tab on the volumes and materials panel

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open the volumes dashboard

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in the volumes dashboard, the panel on the left will show the total site volume

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to turn this on. Click on the toggle net graph button on the top left of the dashboard.

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Now we'll create a volume surface for the road.

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Click on the create new volume surface button as shown

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for the name

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use vol to sycamore heights datum

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set the style to cut and fill banding. One for interval

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two D.

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The base surface is always the existing surface. In our case, existing ground,

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the comparison surface is always the design surface.

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This will be sycamore heights, datum surface

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click OK. And the volume surface will be added to the volumes dashboard.

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It has calculated a net volume of nearly 12,000 cubic yards of cut.

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This means that our profile for the road is generally too low.

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If you pick the profile, you can see the two crests curves are very close together

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to be able to adjust the profile. We will need to reduce the lengths of these curves,

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use the grips on the curves to make them both shorter. As shown.

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This will provide some space between the curves for them to move freely

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at the start of the profile. You can see the change of grade at the intersection.

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If we alter the first grade on sycamore heights,

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there is a possibility that the dynamic intersection will add a new tangent.

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We want to avoid this. So review the rules for the intersection,

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right, click on the intersection in prospector

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and select a just side road profile.

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The rules show that the maximum grade into the intersection is five per cent

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and the maximum change in grade is 4%

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since the cross fall on the main road is at minus 1.94%.

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This allows us a maximum grade of 2.06% on the incoming tangent.

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Right. Click on the profile and select edit profile geometry

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on the profile out tools

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open the profile grid view

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in the grid view, set the grade of the tangent in the grade out column

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to 2.05 per cent as shown.

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Since we know we can't raise that tangent or its intersection point,

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then we must use the PV I of the second curve to adjust our volumes

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using the grips on the profile,

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pick the PV I grip and drag it up

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after the corridor has rebuilt.

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Go back to the volumes dashboard

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by switching tabs in the Panorama viewer

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use the recompute volumes button to refresh the volume surface.

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I still have a net cut of 1963 cubic yards.

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You'll have different values depending on the edits you've made,

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you can repeat the adjustment to the profile to

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reduce the net volume as much as you can.

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I'm going to edit the profile again

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and then go back to the profile grid view.

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I want to reset the K value of the curve. I've changed back to 151

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close the profile layout tools and the profile grid view

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reopen the volumes dashboard if it is closed,

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use the recompute volumes button to refresh the volume surface.

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In our example, we now have 1052 cubic yards of fill.

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Again, your volume will be different depending on the changes you have made.

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You can readjust the profile as before

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to reduce the net volume even further.

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Now we'll update the surface style to display our cut and fills

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in the model. Pick the blue volume surface,

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bright click and select surface properties

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in the surface properties. Go to the analysis tab

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The analysis type should be set to elevations

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for the legend, select cut and fill volumes

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for the ranges, select range interval with data.

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The interval will be 1 ft

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and the datum will be zero.

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Use the run analysis button to generate the ranges

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cut areas will be displayed in reds and the fill areas will be displayed in greens.

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Click. OK?

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We can now see visually where the cotton field takes place on our road.

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A groundworks contractor could use a drawing of this

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to plan where to dig and where to place to cut material,

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select the volume surface.

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And on the surface ribbon tab labels and tables panel, select a legend

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on the command line, choose elevations for the table type

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and then choose dynamic for the table behavior.

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Select a position for the legend table in the upper viewport

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somewhere clear of the design.

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The legend displays the cup fill depths

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with the color

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and two D area and the volume for each color band.

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Finally, in this example, I have added all three volume surfaces,

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one for each corridor

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to the volumes dashboard.

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The total net volume for all three roads is shown as 43,000 cubic yards of cut.

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The volumes dashboard allows me to trade volumes across all three corridors.

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It may not be possible to raise one road because of design constraints,

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but I might be able to raise one of the others to compensate.

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After making some more edits to my corridors. I've been able to reduce the volume

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to 18 178 cubic yards of cut.

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We have seen how we can use volume surfaces and the volumes dashboard

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to optimize our red design

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using the volume surface style. We can display a cut and fill analysis graphically

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and the legend adds detail to our analysis.