• Civil 3D

Grade a site using grading objects

Create a grading group, use the Grading Creation Tools to create and modify grading objects, and use the Grading Volume Tools for grading optimization in Civil 3D.


00:04

Grading objects in Civil 3D can be used for a variety of terrain modification and land development tasks

00:10

that require exact control over slopes and elevations.

00:14

Common applications include creating level building pads,

00:18

designing detention or retention ponds that manage stormwater runoff effectively,

00:23

and shaping landscapes, roadway embankments, and more

00:28

to ensure proper drainage and sustainability.

00:31

To demonstrate the use of grading objects,

00:34

a previously created drawing is already open in Civil 3D.

00:39

An added feature line already has elevations assigned

00:42

and will be used as the base of the design.

00:45

On the Home tab, Create Design panel, expand Grading Object

00:51

and select Grading Creation Tools.

00:54

This displays the Grading Creation Tools toolbar,

00:57

where you can set up your grading object by working from left to right across the toolbar.

01:03

First, click Set the Grading Group.

01:06

In this example, there are no current grading groups,

01:10

so a new one needs to be created.

01:12

Enter a Name, such as “Pond”, enable Automatic surface creation,

01:17

and leave the Surface style setting as is.

01:20

If you want to check the volume,

01:22

enable Volume base surface,

01:24

and then set the Base surface—here, existing ground, or EG, is selected.

01:30

Click OK.

01:32

In the Create Surface dialog, leave the default name,

01:37

which is the same as the grading group name, and then click OK to create the surface.

01:43

In the Grading Creation Tools toolbar, notice that the Group is now set to Pond

01:48

and the volume Surface is set to existing ground.

01:52

The surface is already set, so you do not need to set the target surface.

01:57

Grading layers are also not required due to the styles that are set.

02:02

Click Select a Criteria Set, and since the Basic Set has everything required here, simply click OK.

02:10

Then, expand the Criteria drop-down and select a criteria.

02:16

In this case, select Grade to Distance to create a semi-flat surface on top of the pond.

02:22

Next, expand the Grading Creation Tools drop-down and select Create Grading.

02:28

When prompted, select the feature line, then click inside to grade that area first.

02:34

Click Yes to apply the grading to the entire length.

02:40

To specify a distance, you can either select a point in the drawing or type an exact distance.

02:47

Here, type 3, and then press Enter.

02:52

Finally, set the Format.

02:56

For this example, since you want the grading to have a -2% slope to the inside of the pond, select Grade,

03:03

and then enter -2.

03:06

The surface is generated.

03:09

Press ESC to complete the command.

03:12

To review the grading object in 3D, right-click the surface and select Object Viewer.

03:19

In the Object Viewer, pan and orbit the drawing to see that the grading is sloping into the inside of the pond.

03:27

Next, apply a grade to the outside of the pond.

03:31

From the Grading Creation Tools, expand the Criteria drop-down,

03:35

and this time, select Grade to Surface.

03:39

Click Create Grading.

03:42

Select the feature line, pick a point to grade the area outside of the pond,

03:47

and apply the grade to the entire length.

03:51

Set the Cut Format to Slope, and press ENTER to accept a 2.00 : 1 slope.

03:58

Then, set the Fill Format Slope to 3.00 : 1.

04:03

The surface is created.

04:06

Open the Object Viewer again to see the grading outside of the pond,

04:11

with a slight rim at the top,

04:13

but with no triangles or contours in the center.

04:17

This is because an infill needs to be added.

04:21

First, however, you need to set the depth of the pond.

04:24

Back in the toolbar, set the Criteria to Grade to Relative Elevation,

04:29

and then click Create Grading.

04:32

Select the inside line of the grading object as the feature line and apply the grading to the entire length.

04:40

Specify a Relative Elevation of -3 for a pond depth of 3 feet,

04:44

and then set the Format to a Slope of 2.00 : 1,

04:48

making it the same on both sides.

04:51

Press ENTER to finish the command.

04:55

Reviewing the surface in the Object Viewer, it now looks like a pond,

05:00

but you still need to add an infill.

05:03

From the toolbar, expand the Create Grading drop-down and select Create Infill.

05:10

In the drawing, pick a point on the inside, then press ENTER.

05:16

Now, in the Object Viewer, you see that it has the triangles to the inside.

05:22

With the surface completely infilled, you can optimize the grading.

05:26

From the toolbar, expand the Grading Utilities drop-down and select Grading Volume Tools.

05:34

The Grading Volume Tools open and display the Cut, Fill, and Net Volumes.

05:41

Here, you can click Lower the Grading Group to slowly reduce the amount of fill.

05:47

Even better, to balance the Cut and Fill towards a target net volume,

05:51

click Automatically Raise/lower to Balance Volumes.

05:55

The Auto-Balance Volumes dialog opens.

05:59

In this case, leave the Required volume set to 0 cubic yards and click OK.

06:06

After a moment, the grading object changes.

06:09

Select the object, then open the Object Viewer.

06:13

There is now both cut and fill going around the outside of the pond,

06:17

and the inside has an even, 3-foot depth.

06:21

Now you can use the Grading Creation Tools to create and modify grading objects in Civil 3D.

Video transcript

00:04

Grading objects in Civil 3D can be used for a variety of terrain modification and land development tasks

00:10

that require exact control over slopes and elevations.

00:14

Common applications include creating level building pads,

00:18

designing detention or retention ponds that manage stormwater runoff effectively,

00:23

and shaping landscapes, roadway embankments, and more

00:28

to ensure proper drainage and sustainability.

00:31

To demonstrate the use of grading objects,

00:34

a previously created drawing is already open in Civil 3D.

00:39

An added feature line already has elevations assigned

00:42

and will be used as the base of the design.

00:45

On the Home tab, Create Design panel, expand Grading Object

00:51

and select Grading Creation Tools.

00:54

This displays the Grading Creation Tools toolbar,

00:57

where you can set up your grading object by working from left to right across the toolbar.

01:03

First, click Set the Grading Group.

01:06

In this example, there are no current grading groups,

01:10

so a new one needs to be created.

01:12

Enter a Name, such as “Pond”, enable Automatic surface creation,

01:17

and leave the Surface style setting as is.

01:20

If you want to check the volume,

01:22

enable Volume base surface,

01:24

and then set the Base surface—here, existing ground, or EG, is selected.

01:30

Click OK.

01:32

In the Create Surface dialog, leave the default name,

01:37

which is the same as the grading group name, and then click OK to create the surface.

01:43

In the Grading Creation Tools toolbar, notice that the Group is now set to Pond

01:48

and the volume Surface is set to existing ground.

01:52

The surface is already set, so you do not need to set the target surface.

01:57

Grading layers are also not required due to the styles that are set.

02:02

Click Select a Criteria Set, and since the Basic Set has everything required here, simply click OK.

02:10

Then, expand the Criteria drop-down and select a criteria.

02:16

In this case, select Grade to Distance to create a semi-flat surface on top of the pond.

02:22

Next, expand the Grading Creation Tools drop-down and select Create Grading.

02:28

When prompted, select the feature line, then click inside to grade that area first.

02:34

Click Yes to apply the grading to the entire length.

02:40

To specify a distance, you can either select a point in the drawing or type an exact distance.

02:47

Here, type 3, and then press Enter.

02:52

Finally, set the Format.

02:56

For this example, since you want the grading to have a -2% slope to the inside of the pond, select Grade,

03:03

and then enter -2.

03:06

The surface is generated.

03:09

Press ESC to complete the command.

03:12

To review the grading object in 3D, right-click the surface and select Object Viewer.

03:19

In the Object Viewer, pan and orbit the drawing to see that the grading is sloping into the inside of the pond.

03:27

Next, apply a grade to the outside of the pond.

03:31

From the Grading Creation Tools, expand the Criteria drop-down,

03:35

and this time, select Grade to Surface.

03:39

Click Create Grading.

03:42

Select the feature line, pick a point to grade the area outside of the pond,

03:47

and apply the grade to the entire length.

03:51

Set the Cut Format to Slope, and press ENTER to accept a 2.00 : 1 slope.

03:58

Then, set the Fill Format Slope to 3.00 : 1.

04:03

The surface is created.

04:06

Open the Object Viewer again to see the grading outside of the pond,

04:11

with a slight rim at the top,

04:13

but with no triangles or contours in the center.

04:17

This is because an infill needs to be added.

04:21

First, however, you need to set the depth of the pond.

04:24

Back in the toolbar, set the Criteria to Grade to Relative Elevation,

04:29

and then click Create Grading.

04:32

Select the inside line of the grading object as the feature line and apply the grading to the entire length.

04:40

Specify a Relative Elevation of -3 for a pond depth of 3 feet,

04:44

and then set the Format to a Slope of 2.00 : 1,

04:48

making it the same on both sides.

04:51

Press ENTER to finish the command.

04:55

Reviewing the surface in the Object Viewer, it now looks like a pond,

05:00

but you still need to add an infill.

05:03

From the toolbar, expand the Create Grading drop-down and select Create Infill.

05:10

In the drawing, pick a point on the inside, then press ENTER.

05:16

Now, in the Object Viewer, you see that it has the triangles to the inside.

05:22

With the surface completely infilled, you can optimize the grading.

05:26

From the toolbar, expand the Grading Utilities drop-down and select Grading Volume Tools.

05:34

The Grading Volume Tools open and display the Cut, Fill, and Net Volumes.

05:41

Here, you can click Lower the Grading Group to slowly reduce the amount of fill.

05:47

Even better, to balance the Cut and Fill towards a target net volume,

05:51

click Automatically Raise/lower to Balance Volumes.

05:55

The Auto-Balance Volumes dialog opens.

05:59

In this case, leave the Required volume set to 0 cubic yards and click OK.

06:06

After a moment, the grading object changes.

06:09

Select the object, then open the Object Viewer.

06:13

There is now both cut and fill going around the outside of the pond,

06:17

and the inside has an even, 3-foot depth.

06:21

Now you can use the Grading Creation Tools to create and modify grading objects in Civil 3D.

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