• Civil 3D

Build an existing ground surface

Create an existing ground surface and add data to that surface.


00:04

We're now going to start building our existing ground surface from

00:07

project data that we've acquired from a variety of sources.

00:13

This existing ground surface will be the base drawing for all of our site design.

00:17

From this point onwards.

00:21

In this drawing,

00:21

we have the survey points point group which was created from our survey point file.

00:28

We also have some contours which have been extracted from

00:31

ad em model from the US geographical survey data.

00:36

These are just lightweight poly lines with the height

00:40

to create a new surface. We could use the home ribbon tab

00:44

and on the crate ground data panel, choose surfaces and then create surface.

00:49

However,

00:50

we are going to use prospector to create our surface since

00:54

this provides easy access for everything that we need to do

00:58

in prospector, right, click on the surfaces collection and choose create surface.

01:05

This surface will be a tin surface made up of irregular triangles,

01:10

override the default name and rename it to existing ground.

01:15

It's good practice to give your civil 3d

01:17

objects names that your co workers will understand.

01:21

You can enter a description if required

01:24

set the surface style to contours 1 ft and 5 ft design.

01:29

This will show colored contours at 1 ft intervals.

01:33

Click OK.

01:36

We've just created a new empty surface. Now we need to start adding data to it.

01:41

We can add data to a surface using the ribbon

01:45

on the modify ribbon tab from the ground data panel, choose surface.

01:50

Then on the surface ribbon tab from the modify panel,

01:54

there's an add data button which can be used

01:56

to add data of different types to the surface.

01:60

We can also add data to our surface using the tool space prospector tap,

02:05

expand the existing ground surface in the surfaces collection,

02:10

expand the definition item.

02:13

Here you'll see all the different methods of adding data to the surface.

02:19

First, we're going to add our COGO points,

02:22

right. Click on point groups, select add

02:25

and from the list of point groups, choose survey points and then click. OK.

02:31

You will see the data has been added to the surface

02:34

and the surface is displayed in the model space as contours.

02:39

Now we're going to add the contour poly lines to the surface.

02:44

This is going to provide less accurate

02:46

surface data around the immediate site boundary.

02:49

But we can use this additional area of surface to provide context to our project.

02:56

Select the contours item, right click and choose add,

03:01

enter the description contours from dem

03:06

each contour will have a lot of vertices along the line and

03:10

this will subsequently generate a large number of triangles in the surface

03:15

which could affect the performance of our models.

03:18

We can adjust the number of vertices that are added from

03:21

the contour poly lines using the weeding and supplementing factors.

03:27

The weeding factors control the removal of points from the contour.

03:31

If the distance between vertices on two

03:34

line segments is less than the weeding distance

03:37

then provided the deviation of line segments is less than the weeding angle.

03:42

The middle vertex will be deleted.

03:45

Supplementing factors control the insertion of interpolated points

03:50

to ensure similarly sized triangles are created.

03:54

If the distance between two contour vertices

03:56

is greater than the supplementing distance,

03:59

then additional vertices are added.

04:02

If the contour lines are curved,

04:04

then additional vertices may be added around the curve so

04:07

that our surface triangles will match the contour more accurately

04:12

if the mid ordinate distance of the curved segment between

04:16

two vertices is greater than the supplementing mid ordinate distance,

04:20

then additional vertices are added

04:22

so that the separation of surface triangle sides are

04:25

now curved will match the specified mid ordinate distance

04:31

in the minimized flat areas by section

04:34

select swapping edges.

04:38

This ensures that triangles will be rearranged to prevent triangles from

04:42

spanning a single value contour and thus creating a flat triangle

04:47

click. OK. And in the model space use a crossing window

04:51

to select all of the contours

04:54

press enter to accept the selection.

04:57

The contours are now added to the surface definition.

05:00

We can't delete the original poly lines as this will delete them from the surface.

05:05

So to prevent us selecting them again, by accident, we'll turn off their layers

05:11

from the home ribbon tab on the layers panel,

05:13

click on the layers pull down list and turn off the layers zero D

05:18

contours major

05:19

and zero dem contours minor.

05:22

By turning off the light bulb icon.

05:25

We're now going to add some brake lines

05:26

to our surface to improve the surface definition.

05:30

When we add brake lines to a surface civil 3D will re triangulate the surface

05:35

to ensure that our surface triangle sides lie along the brake line and don't cross it

05:43

from the insert ribbon tab on the block panel,

05:45

choose insert and select blocks from libraries.

05:50

Add a new library by picking the add a library button

05:54

from the library. Now displayed, we're going to insert the 3D brake lines drawing

05:59

first, ensure that none of the insertion options are selected.

06:03

Right? Click on the 3D brake lines, drawing and choose insert and explode.

06:10

The brake lines are inserted into the drawing.

06:13

These are 3d poly lines representing surveyed features on the ground

06:19

in prospector, select brake lines from the existing ground definition,

06:24

right click and choose add,

06:27

enter a description of 3D survey.

06:32

There are two main types of brake lines standard and proximity.

06:37

We use standard when our brake lines are 3D and we

06:40

want to add the brake line heights to the surface.

06:45

We use proximity when our brake lines are two D poly

06:47

lines.

06:49

In this case, civil 3d will ignore the Z value of the Polyline

06:53

and only use the xy position of the line to control the triangles

06:58

ensure the brake line type is set to standard and click. Ok.

07:02

In the model space use a window crossing to select all

07:05

of the brake lines and press enter to accept the selection.

07:10

The brake lines will be added to the surface and the contours will update

07:15

the event viewer may be invoked by alerts triggered during the surface rebuild.

07:21

You can review warnings in the event viewer

07:23

and zoom to specific issues to review them.

07:27

Some brake lines have not been added where they cross another brake line

07:32

close the event viewer.

07:34

We're now going to add some additional

07:36

survey information from A two D survey drawing

07:39

from the insert ribbon tab blocks panel, select insert then blocks from libraries

07:46

select the two D survey drawing, right click and choose, insert and explode.

07:54

The two D survey has text values to represent the survey levels.

07:60

These have no Z value but the contents of

08:02

the text provides us with the required elevation.

08:07

We can raise these text items up to their correct Z values.

08:12

Select one of the text values right click and choose select similar

08:18

from the modify ribbon tab ground data panel, choose surface

08:24

from the surface ribbon tab surface tools panel select move to surface,

08:29

then move text to elevation.

08:32

The selected text objects will be given Z values based on their text contents.

08:40

Back in prospector under existing ground and definition slit drawing objects.

08:47

We use this method when we want to add data

08:49

to our surface that's represented by existing autocad entities.

08:53

Right? Click and choose add

08:56

from the list of types. Choose the text filter

09:00

type a description of two D level text

09:04

in the model space. Use a window crossing to select the area of two D text

09:09

press enter to accept the selection

09:13

again, the surface will update with the new information we have added.

09:20

We're now going to add the two D features as brake lines.

09:24

In prospector select brake lines, right, click and add

09:28

type a description of two D survey

09:32

set,

09:33

the brake line type to proximity since we don't want

09:36

to use the elevations of the lines in the surface

09:39

and click. Ok.

09:42

Use a crossing window to select all of the

09:44

poly lines in the two D survey and presenter,

09:48

close the event viewer. If it appears

09:53

the result of adding the two D brake lines can be

09:55

seen on this embankment where the contours now run along it.

10:01

Now that we've added our different datasets to the surface, we can review it,

10:06

select the surface by clicking on any contour,

10:09

right click and select object viewer.

10:14

We can see in the 3d view that there are

10:16

some mistakes in the surface which we'll need to correct.

10:21

We've now created our existing ground surface and our next task

10:25

will be to edit the surface to correct any errors.

Video transcript

00:04

We're now going to start building our existing ground surface from

00:07

project data that we've acquired from a variety of sources.

00:13

This existing ground surface will be the base drawing for all of our site design.

00:17

From this point onwards.

00:21

In this drawing,

00:21

we have the survey points point group which was created from our survey point file.

00:28

We also have some contours which have been extracted from

00:31

ad em model from the US geographical survey data.

00:36

These are just lightweight poly lines with the height

00:40

to create a new surface. We could use the home ribbon tab

00:44

and on the crate ground data panel, choose surfaces and then create surface.

00:49

However,

00:50

we are going to use prospector to create our surface since

00:54

this provides easy access for everything that we need to do

00:58

in prospector, right, click on the surfaces collection and choose create surface.

01:05

This surface will be a tin surface made up of irregular triangles,

01:10

override the default name and rename it to existing ground.

01:15

It's good practice to give your civil 3d

01:17

objects names that your co workers will understand.

01:21

You can enter a description if required

01:24

set the surface style to contours 1 ft and 5 ft design.

01:29

This will show colored contours at 1 ft intervals.

01:33

Click OK.

01:36

We've just created a new empty surface. Now we need to start adding data to it.

01:41

We can add data to a surface using the ribbon

01:45

on the modify ribbon tab from the ground data panel, choose surface.

01:50

Then on the surface ribbon tab from the modify panel,

01:54

there's an add data button which can be used

01:56

to add data of different types to the surface.

01:60

We can also add data to our surface using the tool space prospector tap,

02:05

expand the existing ground surface in the surfaces collection,

02:10

expand the definition item.

02:13

Here you'll see all the different methods of adding data to the surface.

02:19

First, we're going to add our COGO points,

02:22

right. Click on point groups, select add

02:25

and from the list of point groups, choose survey points and then click. OK.

02:31

You will see the data has been added to the surface

02:34

and the surface is displayed in the model space as contours.

02:39

Now we're going to add the contour poly lines to the surface.

02:44

This is going to provide less accurate

02:46

surface data around the immediate site boundary.

02:49

But we can use this additional area of surface to provide context to our project.

02:56

Select the contours item, right click and choose add,

03:01

enter the description contours from dem

03:06

each contour will have a lot of vertices along the line and

03:10

this will subsequently generate a large number of triangles in the surface

03:15

which could affect the performance of our models.

03:18

We can adjust the number of vertices that are added from

03:21

the contour poly lines using the weeding and supplementing factors.

03:27

The weeding factors control the removal of points from the contour.

03:31

If the distance between vertices on two

03:34

line segments is less than the weeding distance

03:37

then provided the deviation of line segments is less than the weeding angle.

03:42

The middle vertex will be deleted.

03:45

Supplementing factors control the insertion of interpolated points

03:50

to ensure similarly sized triangles are created.

03:54

If the distance between two contour vertices

03:56

is greater than the supplementing distance,

03:59

then additional vertices are added.

04:02

If the contour lines are curved,

04:04

then additional vertices may be added around the curve so

04:07

that our surface triangles will match the contour more accurately

04:12

if the mid ordinate distance of the curved segment between

04:16

two vertices is greater than the supplementing mid ordinate distance,

04:20

then additional vertices are added

04:22

so that the separation of surface triangle sides are

04:25

now curved will match the specified mid ordinate distance

04:31

in the minimized flat areas by section

04:34

select swapping edges.

04:38

This ensures that triangles will be rearranged to prevent triangles from

04:42

spanning a single value contour and thus creating a flat triangle

04:47

click. OK. And in the model space use a crossing window

04:51

to select all of the contours

04:54

press enter to accept the selection.

04:57

The contours are now added to the surface definition.

05:00

We can't delete the original poly lines as this will delete them from the surface.

05:05

So to prevent us selecting them again, by accident, we'll turn off their layers

05:11

from the home ribbon tab on the layers panel,

05:13

click on the layers pull down list and turn off the layers zero D

05:18

contours major

05:19

and zero dem contours minor.

05:22

By turning off the light bulb icon.

05:25

We're now going to add some brake lines

05:26

to our surface to improve the surface definition.

05:30

When we add brake lines to a surface civil 3D will re triangulate the surface

05:35

to ensure that our surface triangle sides lie along the brake line and don't cross it

05:43

from the insert ribbon tab on the block panel,

05:45

choose insert and select blocks from libraries.

05:50

Add a new library by picking the add a library button

05:54

from the library. Now displayed, we're going to insert the 3D brake lines drawing

05:59

first, ensure that none of the insertion options are selected.

06:03

Right? Click on the 3D brake lines, drawing and choose insert and explode.

06:10

The brake lines are inserted into the drawing.

06:13

These are 3d poly lines representing surveyed features on the ground

06:19

in prospector, select brake lines from the existing ground definition,

06:24

right click and choose add,

06:27

enter a description of 3D survey.

06:32

There are two main types of brake lines standard and proximity.

06:37

We use standard when our brake lines are 3D and we

06:40

want to add the brake line heights to the surface.

06:45

We use proximity when our brake lines are two D poly

06:47

lines.

06:49

In this case, civil 3d will ignore the Z value of the Polyline

06:53

and only use the xy position of the line to control the triangles

06:58

ensure the brake line type is set to standard and click. Ok.

07:02

In the model space use a window crossing to select all

07:05

of the brake lines and press enter to accept the selection.

07:10

The brake lines will be added to the surface and the contours will update

07:15

the event viewer may be invoked by alerts triggered during the surface rebuild.

07:21

You can review warnings in the event viewer

07:23

and zoom to specific issues to review them.

07:27

Some brake lines have not been added where they cross another brake line

07:32

close the event viewer.

07:34

We're now going to add some additional

07:36

survey information from A two D survey drawing

07:39

from the insert ribbon tab blocks panel, select insert then blocks from libraries

07:46

select the two D survey drawing, right click and choose, insert and explode.

07:54

The two D survey has text values to represent the survey levels.

07:60

These have no Z value but the contents of

08:02

the text provides us with the required elevation.

08:07

We can raise these text items up to their correct Z values.

08:12

Select one of the text values right click and choose select similar

08:18

from the modify ribbon tab ground data panel, choose surface

08:24

from the surface ribbon tab surface tools panel select move to surface,

08:29

then move text to elevation.

08:32

The selected text objects will be given Z values based on their text contents.

08:40

Back in prospector under existing ground and definition slit drawing objects.

08:47

We use this method when we want to add data

08:49

to our surface that's represented by existing autocad entities.

08:53

Right? Click and choose add

08:56

from the list of types. Choose the text filter

09:00

type a description of two D level text

09:04

in the model space. Use a window crossing to select the area of two D text

09:09

press enter to accept the selection

09:13

again, the surface will update with the new information we have added.

09:20

We're now going to add the two D features as brake lines.

09:24

In prospector select brake lines, right, click and add

09:28

type a description of two D survey

09:32

set,

09:33

the brake line type to proximity since we don't want

09:36

to use the elevations of the lines in the surface

09:39

and click. Ok.

09:42

Use a crossing window to select all of the

09:44

poly lines in the two D survey and presenter,

09:48

close the event viewer. If it appears

09:53

the result of adding the two D brake lines can be

09:55

seen on this embankment where the contours now run along it.

10:01

Now that we've added our different datasets to the surface, we can review it,

10:06

select the surface by clicking on any contour,

10:09

right click and select object viewer.

10:14

We can see in the 3d view that there are

10:16

some mistakes in the surface which we'll need to correct.

10:21

We've now created our existing ground surface and our next task

10:25

will be to edit the surface to correct any errors.

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