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Integrated BIM tools, including Revit, AutoCAD, and Civil 3D
Professional CAD/CAM tools built on Inventor and AutoCAD
Create a TIN surface from survey data, and add breaklines to a surface.
Type:
Tutorial
Length:
3 min.
Transcript
00:03
One of two primary surface types offered by Civil 3D is the triangulated irregular network, or TIN,
00:10
which is constructed from a network of triangles,
00:13
providing a highly detailed and flexible representation of the terrain.
00:18
To create a TIN surface in 3D, begin with an open drawing that includes points from a survey.
00:24
This example also includes 3D feature lines, created from road center lines,
00:29
which will act as breaklines on the surface.
00:32
Breaklines force surface triangulation along the breakline,
00:36
preventing triangulation across the breakline.
00:40
To create a surface in Civil 3D, from the ribbon, Home tab, Create Ground Data panel,
00:46
expand Surfaces, and select Create Surface.
00:51
A Create Surface dialog appears.
00:54
To set the type of surface you wish to create, use the Type: drop-down.
00:59
In this example, the surface will be created from survey data,
01:03
so TIN surface is selected.
01:06
Next, enter a Name, such as “EG” for existing ground,
01:10
and then adjust the Description, Style, and Render Material as necessary.
01:17
Click OK.
01:19
In the Toolspace, Prospector tab,
01:23
expand the Surfaces folder to see that a new folder has been created for the EG surface.
01:28
Expand the folder, which contains Mass, Watersheds, and Definition.
01:34
Then, expand Definition to see all of the types of items that can be added to the surface.
01:40
Here, add a point group that was created previously to isolate the ground shots for the surface.
01:47
Right-click Point Groups and select Add.
01:51
In the Point Groups dialog, select the TOPO point group, and then click OK.
01:57
Immediately, the drawing updates with added contour lines.
02:02
However, you can see that the road centerline is not considered a breakline,
02:07
because the contours are continuing, rather than peaking, at this line.
02:12
You can fix this by adding a breakline.
02:15
In the Toolspace, Prospector tab, right-click Breaklines and select Add.
02:22
In the Add Breaklines dialog, enter a Description, such as “CLRoad” for the centerline of the road.
02:30
Expand the Type drop-down and select Standard,
02:33
because this type will enable triangulation right up to the breakline.
02:38
Click OK.
02:40
You are prompted to select an object in the drawing to set as a breakline.
02:45
Select one or more breaklines that you want to add,
02:48
and then press ENTER to complete the command.
02:52
Zoom in to the drawing, and notice that the centerline is now acting as a breakline,
02:57
with the contours visibly breaking at the line.
03:01
Now you can create a TIN surface from survey data and add breaklines to the surface.
Video transcript
00:03
One of two primary surface types offered by Civil 3D is the triangulated irregular network, or TIN,
00:10
which is constructed from a network of triangles,
00:13
providing a highly detailed and flexible representation of the terrain.
00:18
To create a TIN surface in 3D, begin with an open drawing that includes points from a survey.
00:24
This example also includes 3D feature lines, created from road center lines,
00:29
which will act as breaklines on the surface.
00:32
Breaklines force surface triangulation along the breakline,
00:36
preventing triangulation across the breakline.
00:40
To create a surface in Civil 3D, from the ribbon, Home tab, Create Ground Data panel,
00:46
expand Surfaces, and select Create Surface.
00:51
A Create Surface dialog appears.
00:54
To set the type of surface you wish to create, use the Type: drop-down.
00:59
In this example, the surface will be created from survey data,
01:03
so TIN surface is selected.
01:06
Next, enter a Name, such as “EG” for existing ground,
01:10
and then adjust the Description, Style, and Render Material as necessary.
01:17
Click OK.
01:19
In the Toolspace, Prospector tab,
01:23
expand the Surfaces folder to see that a new folder has been created for the EG surface.
01:28
Expand the folder, which contains Mass, Watersheds, and Definition.
01:34
Then, expand Definition to see all of the types of items that can be added to the surface.
01:40
Here, add a point group that was created previously to isolate the ground shots for the surface.
01:47
Right-click Point Groups and select Add.
01:51
In the Point Groups dialog, select the TOPO point group, and then click OK.
01:57
Immediately, the drawing updates with added contour lines.
02:02
However, you can see that the road centerline is not considered a breakline,
02:07
because the contours are continuing, rather than peaking, at this line.
02:12
You can fix this by adding a breakline.
02:15
In the Toolspace, Prospector tab, right-click Breaklines and select Add.
02:22
In the Add Breaklines dialog, enter a Description, such as “CLRoad” for the centerline of the road.
02:30
Expand the Type drop-down and select Standard,
02:33
because this type will enable triangulation right up to the breakline.
02:38
Click OK.
02:40
You are prompted to select an object in the drawing to set as a breakline.
02:45
Select one or more breaklines that you want to add,
02:48
and then press ENTER to complete the command.
02:52
Zoom in to the drawing, and notice that the centerline is now acting as a breakline,
02:57
with the contours visibly breaking at the line.
03:01
Now you can create a TIN surface from survey data and add breaklines to the surface.
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