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Learn about surfaces, surface types, volume surfaces breaklines and styles.
Type:
Tutorial
Length:
7 min.
Transcript
00:03
Surfaces are used in civil 3D to create a 3d representation of the ground.
00:08
They are made up of triangles or grids which are formed by joining up
00:18
A typical project will require a model of existing conditions.
00:23
We generally create an existing ground
00:24
surface from topographical survey information.
00:27
So we have a model in 3D, we can base our design upon
00:31
whilst we use surfaces to represent our original ground.
00:34
We also create services for designed ground forms such as ponds, building pads,
00:39
car parks and road surfaces.
00:42
Grading groups in civil 3d provide criteria
00:45
based grading design that creates surfaces automatically.
00:50
We also use surfaces directly for designing on.
00:52
In
00:52
this example, we are creating a surface profile to display in a profile view.
00:59
The profile is dynamically linked to the ground surface and will update if
01:03
either the route of the road or the surface elevations have changed.
01:07
Once we have a profile view drawn in the model to display the profile,
01:11
we can lay out the proposed vertical design for the road
01:14
using the surface profile to guide our design.
01:19
A tin surface is made up of triangles and
01:22
can be created using different types of data.
01:25
Tin stands for triangular irregular network
01:29
points and contours often provide the primary data used to create services
01:34
with brake lines used to control the formation of the triangulation.
01:39
Brake lines are ground features such as the top or bottom of an embankment
01:43
edges of roads, ditches and so on
01:46
and will reorganize the triangles in the surface so
01:49
that the triangle sides are aligned with the brake light
01:52
providing a more accurate surface representation.
01:59
A grid surface is created by importing D files or digital elevation model
02:03
files which are typically a grid of heights scanned from an aircraft,
02:08
sometimes called lidar
02:09
data.
02:10
This type of data is widely and often freely available
02:14
and is useful to provide us with
02:16
large areas of surface where conventional topographical survey
02:20
would be too costly or difficult.
02:26
The de file contains a regular grid of elevations
02:30
and large surfaces can be generated very quickly.
02:34
They are considered to be a type of raster data
02:36
like an image with each pixel being an elevation.
02:40
These large surface files can be used in our models to provide context for our design
02:45
and are useful for creating visualizations of our projects.
02:51
We can create surfaces from our designed road corridors.
02:55
These are tin services that are linked to the corridor
02:58
and they are built by adding links and feature lines
03:00
from our assemblies and the corridor model that uses them
03:05
when a corridor is edited. The surface will update automatically.
03:11
We will often create a top surface for our
03:13
road to show contours of the finished road surface.
03:16
And for visualization,
03:19
we can also create a formation or datum surface from our corridor
03:23
that shows the depth of construction for the road.
03:26
And we can use this to calculate earthworks cut and fill.
03:32
The display of a surface is controlled by its style.
03:36
Surface styles can be applied to view surface contours with different intervals.
03:40
For example,
03:42
the style controls which components of the surface points, triangles contours,
03:46
elevations or slopes are displayed
03:49
and they can be set independently for viewing in plan or in 3d.
03:54
We can also use stars to analyze a surface.
03:58
In this example, we are analyzing the surface by height range.
04:03
The surface style allows us to understand information about the surface.
04:07
Without direct interrogation
04:10
legend tables provide further information about our services.
04:17
Like most other civil 3d objects,
04:18
we can add annotations to our surfaces using different label styles.
04:24
Elevation labels provide height information at important locations
04:30
and are useful when we are producing our construction documentation
04:35
contour labels can be added across a surface
04:38
so that we can interpret the surface contours quickly.
04:43
All of these labels are dynamic and will update if our design surfaces change.
04:49
This is important as it means we can
04:50
produce documentation earlier in the project life cycle
04:54
and we don't have to worry about out of date information.
04:59
The format of our labels can be swapped easily.
05:02
These slope labels are being added either as a slope of
05:05
one in X or as a percentage gradient on flatter slopes.
05:12
A special type of surface called a volume
05:15
surface is used to compare two surfaces together
05:18
to calculate volumes of earthworks cut and fill.
05:23
Unlike a normal tin surface, a volume surface is built from depths not elevations.
05:31
These values are derived by subtracting a base surface from a comparison surface
05:42
individual volume surfaces can be combined to give a complete site volume.
05:48
We can use volume surfaces from different design objects
05:52
to balance the whole site cut and fill.
05:56
Volume surfaces contain the information about their depths and volumes.
06:03
This information can be used to produce a surface analysis of the cut and fill
06:07
or Isopack
06:08
its as they are sometimes called.
06:12
Here, we are using a surface style
06:14
that can be analyzed to produce red and green depth
06:17
bands representing the areas of either cut or fill.
06:24
Adding a legend table can provide the empirical information we need
06:28
to make sense of the surface display.
06:31
This type of information can be invaluable for construction planning.
06:36
Now that you have seen how you can build surfaces in civil 3d and how they can be used.
06:41
You are ready to explore the options for
06:43
creating your own existing and design surfaces.
Video transcript
00:03
Surfaces are used in civil 3D to create a 3d representation of the ground.
00:08
They are made up of triangles or grids which are formed by joining up
00:18
A typical project will require a model of existing conditions.
00:23
We generally create an existing ground
00:24
surface from topographical survey information.
00:27
So we have a model in 3D, we can base our design upon
00:31
whilst we use surfaces to represent our original ground.
00:34
We also create services for designed ground forms such as ponds, building pads,
00:39
car parks and road surfaces.
00:42
Grading groups in civil 3d provide criteria
00:45
based grading design that creates surfaces automatically.
00:50
We also use surfaces directly for designing on.
00:52
In
00:52
this example, we are creating a surface profile to display in a profile view.
00:59
The profile is dynamically linked to the ground surface and will update if
01:03
either the route of the road or the surface elevations have changed.
01:07
Once we have a profile view drawn in the model to display the profile,
01:11
we can lay out the proposed vertical design for the road
01:14
using the surface profile to guide our design.
01:19
A tin surface is made up of triangles and
01:22
can be created using different types of data.
01:25
Tin stands for triangular irregular network
01:29
points and contours often provide the primary data used to create services
01:34
with brake lines used to control the formation of the triangulation.
01:39
Brake lines are ground features such as the top or bottom of an embankment
01:43
edges of roads, ditches and so on
01:46
and will reorganize the triangles in the surface so
01:49
that the triangle sides are aligned with the brake light
01:52
providing a more accurate surface representation.
01:59
A grid surface is created by importing D files or digital elevation model
02:03
files which are typically a grid of heights scanned from an aircraft,
02:08
sometimes called lidar
02:09
data.
02:10
This type of data is widely and often freely available
02:14
and is useful to provide us with
02:16
large areas of surface where conventional topographical survey
02:20
would be too costly or difficult.
02:26
The de file contains a regular grid of elevations
02:30
and large surfaces can be generated very quickly.
02:34
They are considered to be a type of raster data
02:36
like an image with each pixel being an elevation.
02:40
These large surface files can be used in our models to provide context for our design
02:45
and are useful for creating visualizations of our projects.
02:51
We can create surfaces from our designed road corridors.
02:55
These are tin services that are linked to the corridor
02:58
and they are built by adding links and feature lines
03:00
from our assemblies and the corridor model that uses them
03:05
when a corridor is edited. The surface will update automatically.
03:11
We will often create a top surface for our
03:13
road to show contours of the finished road surface.
03:16
And for visualization,
03:19
we can also create a formation or datum surface from our corridor
03:23
that shows the depth of construction for the road.
03:26
And we can use this to calculate earthworks cut and fill.
03:32
The display of a surface is controlled by its style.
03:36
Surface styles can be applied to view surface contours with different intervals.
03:40
For example,
03:42
the style controls which components of the surface points, triangles contours,
03:46
elevations or slopes are displayed
03:49
and they can be set independently for viewing in plan or in 3d.
03:54
We can also use stars to analyze a surface.
03:58
In this example, we are analyzing the surface by height range.
04:03
The surface style allows us to understand information about the surface.
04:07
Without direct interrogation
04:10
legend tables provide further information about our services.
04:17
Like most other civil 3d objects,
04:18
we can add annotations to our surfaces using different label styles.
04:24
Elevation labels provide height information at important locations
04:30
and are useful when we are producing our construction documentation
04:35
contour labels can be added across a surface
04:38
so that we can interpret the surface contours quickly.
04:43
All of these labels are dynamic and will update if our design surfaces change.
04:49
This is important as it means we can
04:50
produce documentation earlier in the project life cycle
04:54
and we don't have to worry about out of date information.
04:59
The format of our labels can be swapped easily.
05:02
These slope labels are being added either as a slope of
05:05
one in X or as a percentage gradient on flatter slopes.
05:12
A special type of surface called a volume
05:15
surface is used to compare two surfaces together
05:18
to calculate volumes of earthworks cut and fill.
05:23
Unlike a normal tin surface, a volume surface is built from depths not elevations.
05:31
These values are derived by subtracting a base surface from a comparison surface
05:42
individual volume surfaces can be combined to give a complete site volume.
05:48
We can use volume surfaces from different design objects
05:52
to balance the whole site cut and fill.
05:56
Volume surfaces contain the information about their depths and volumes.
06:03
This information can be used to produce a surface analysis of the cut and fill
06:07
or Isopack
06:08
its as they are sometimes called.
06:12
Here, we are using a surface style
06:14
that can be analyzed to produce red and green depth
06:17
bands representing the areas of either cut or fill.
06:24
Adding a legend table can provide the empirical information we need
06:28
to make sense of the surface display.
06:31
This type of information can be invaluable for construction planning.
06:36
Now that you have seen how you can build surfaces in civil 3d and how they can be used.
06:41
You are ready to explore the options for
06:43
creating your own existing and design surfaces.
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