civil 3d point and surface

Conservation Applications of LiDAR

Engineering Applications of LiDAR Data

Workshop Exercises

2012

These exercises are part of the “Conservation Applications of LiDAR” project – a series of hands-on workshops designed to help Minnesota GIS specialists effectively use LiDAR-derived data to address natural resource issues. The project is funded by a grant from the Environment

and Natural Resources Trust Fund, and is presented by the University of Minnesota Water Resources Center with expertise provided from the University of Minnesota, MN Department of

Natural Resources, MN Board of Water and Soil Resources, and USDA Natural Resources Conservation Service. More information is at http://tsp.umn.edu/lidar.

2 “Engineering Uses of LiDAR Data” Workshop Exercises

Engineering Applications of LiDAR Data Workshop Exercises

GENERAL NOTES FOR WORKING WITH CIVIL 3D AND GETTING STARTED .............................................. 3

LABELING IN CIVIL 3D ........................................................................................................................... 5

USING PHOTOS AS A BACKGROUND ..................................................................................................... 6

USING POINTS IN CIVIL 3D .................................................................................................................... 8

IMPORTING POINTS FROM LIDAR SOURCES ......................................................................................... 9

Table 1. LIDAR data point options .......................................................................................................... 10

CREATING SURFACES ......................................................................................................................... 14

EDITING SURFACES ............................................................................................................................ 15

Exercise 1: Using DEM data in design.................................................................................................. 21

Exercise 2: Using Shape file data to build a surface ............................................................................ 30

Exercise 3: Working with a geodatabase to build a surface ................................................................ 32

Exercise 4: Using LAS files to build a surface ...................................................................................... 36


GENERAL NOTES FOR WORKING WITH CIVIL 3D AND GETTING STARTED

First, start a new drawing using the template option: File New Select the AutoCAD Civil 3D Imperial template file:

Using a generic template file is a good choice because the layers and settings for label styles, etc. are already created. Your agency may have its own template that is to be used. All of the project elements are controlled and accessed through the “Toolspace”. This panel is located in the upper left hand corner of the Civil 3D screen. Within the Toolspace, there is a “Prospector” tab and a “Settings” tab.


1. Using the Prospector

2. Using the Settings tab Set the coordinate system for your drawing right away, before doing any work. This is done as a “Project Setting”. To do this, follow these steps:

1. Select the “settings tab” on the Prospector 2. Right click on the drawing name and select “Edit Drawing Settings” 3. Select the “Units and Zone” tab. Specify the “Category” and “Available Coordinate System”

as desired Once this is done, any LIDAR data you import will be adjusted for the correct coordinate zone. Importing Styles and Settings If a drawing has been created through other means, or has not been set up using a template file, the template can still be added using the “Manage” tab in Civil 3D. In the “styles” panel, find “Import” then navigate to the template file you desire.


LABELING IN CIVIL 3D

Use either the MTEXT command, or Annotate options MTEXT: type at command prompt, or find on Annotate Tab Or, use auto labeling: First, set up the label styles you need. Find the “Annotate” tab on top See “Add Labels” on far left, and select the label icon on the top. You can also use the “Add Labels” command on the bottom half of the button.

By using the template, the label styles are already created. You can edit them for labeling surfaces and alignments.


USING PHOTOS AS A BACKGROUND

Photos can be added to any project using the “MAPCONNECT” command. This is a good option if you are NOT going to be able to connect to the Internet at all times. To do this, follow the steps below:

1. The county tile is downloaded from the www.mngeo.mn.us website.

2. Find “Air Photos” under the “popular resources” tab on the right

3. Select the “FSA Photos” button

4. Then click on “2010” under the “Download County Files” option

5. Select the county you want. A zip file will download, and you need to bring the “.sid” file into a directory on your hard drive

6. In Civil 3D, type MAPCONNECT, then under the “Add Raster Image” option, select the .sid file you want to bring in, and then click on “CONNECT” and “ADD TO MAP”. Put this photo on its own layer that can be frozen to speed up drafting time.

Other sources of photo background tiles if you will have a live Internet connection:

1. In Civil 3D, type MAPCONNECT, then under the “Add WMS Connection” , specify either of these two WMS connections: http://geoint.lmic.state.mn.us/cgi-bin/wms? for the entire state map or http://geoint.lmic.state.mn.us/cgi-bin/wmsz? for the MN state quadrangle map

2. Click “Connect”

3. At the prompt to “enter user name & password”, leave both fields blank and click “Login”


Then, select the box next to “2010 Schema” and “Add to Map”

4. Use <Shift> and the left mouse to select the image and then use DRAWORDER to move the photo to the back of the drawing.

5. To reduce the size of the raster image: zoom in or out to the size of the photo image you want showing, then, in MapWSpace, right click on “resample raster”. This will be the size until you “resample” again.


USING POINTS IN CIVIL 3D

In AutoCAD Civil 3D, you can create, work with, and manage points using a variety of commands and tools. The points created by AutoCAD Civil 3D are called Coordinate Geometry (COGO) points, which are very different from AutoCAD point nodes. AutoCAD point nodes have only coordinate data (XYZ values) associated with them. However, COGO points, in addition to coordinate data, have a variety of properties associated with them, including point number, point name, raw (field) description, and full (expanded) description. Unlike AutoCAD point nodes, which exist in a single drawing, COGO points can be stored in a project outside a drawing and referenced by multiple users. In AutoCAD Civil 3D, the term point refers to a COGO point, not to an AutoCAD point node. Displaying and Labeling Points

To control the appearance of a point symbol in a drawing, either select a default point symbol, or create a point symbol.

Creating Points Choose from many point creation commands to create points. For more information, see Creating Points. You can also create points by importing point data from a file.


IMPORTING POINTS FROM LIDAR SOURCES

Using AutoCAD Civil 3D, you can import points into a drawing in a variety of ways. Table 1 outlines the point formats that are available as options.

LIDAR data is available from a variety of sources. Standards:

Defined by the MN Digital Elevation Committee Based on the recent USGA Base LIDAR specification < 15 centimeter RMSEs 2-foot vertical accuracy (95%) confidence 1-meter horizontal accuracy

Coordinate System

UTM Zone 15, NAD83 horizontal datum NAVD88 vertical datum (with units in meters)

Make sure to set your coordinate settings in each Civil 3D drawing before working. This is done on the “Prospector” under “Edit Drawing Settings”, and is very important.

You can also transfer points from an ASCII (text) file or a Microsoft® Access database file to another file. You can convert the point data during the transfer, which can include changing the coordinate zone.

Importing points is a quick way to place points into a drawing. For example, if a surveyor collects point data using a data collector, the data can be downloaded from the collector as an ASCII (text) file and then imported into an AutoCAD Civil 3D drawing.

Before you can import, export, or transfer point data, you must specify a point file format for each file that point data is read from or written to. The point file format describes how the point data is stored in the file. You can use the point file formats that are supplied with AutoCAD Civil 3D or create your own formats.


Table1.LIDARdatapointoptions

Sources

LIDAR Data for MN MN Geospatial Information Office: http://www.mngeo.state.mn.us/chouse/elevation/lidar.html For all areas outside the Red River Valley, files can be downloaded for the state, using Filezilla Data is downloaded as a .laz file In Filezilla, specify host: ftp://ftp.lmic.state.mn.us/pub/data/elevation/lidar In “remote site” window, specify “County”, then the county you are looking for. Then, “laz” or “geodatabase”, depending on how you want to use the data. See below for information on File Types For all areas within the Red River Valley, files are downloaded at the DNR Data Deli, located at http://deli.dnr.state.mn.us/data_search.html Files are emailed to users as a .zip file. Data comes in as a “.shp” file File type Source(s) Description Application/notes Geodatabase: .gdb file DEMs: .adf file

lmic.state.mn.us

This is the format that is most typically used Need ArcMAP to convert DEM file and elevations to feet A surface is created that will give elevations BETWEEN contours, which is beneficial for modeling ADF is the file extension for the Arc/Info Binary Grid format. It is one of the two raster GIS (geographic information system) file formats developed by ESRI, the other being the ARC/INFO ASCII Grid format. Whereas the ASCII format is used exclusively as an exchange or export format, the binary format is mainly used within the ESRI programs, like the ArcGIS and ArcView. Note: ARCGIS can be used to convert adf files to feet. Use Spatial Analyst to do that.

Most accurate data ArcGIS can’t make use of a simple .adf file. An ADF file is just a building block for the Arc Grid required. To manipulate the DEM in ArcMAP: 1. Right click on the DEM of interest after loading the full

geodatabase with “add data” 2. Select Data, then Export Data 3. Set Format to Grid 4. Specify location of save 5. Name and make sure the cell size is the same 6. Click save This will create an Arc Grid in the file location you specify, inside of which you can get the .adf files you need.


DEMs continued

Red River Basin http://www.mngeo.state.mn.us/chouse/elevation/lidar.html

Elevation Data Shows up as a contour map Contains elevation of a terrain over a specified area Can be manipulated to create other elevation-dependent data products Consists of pixels or cells Value assigned represents an average elevation of the grid cell Resolution: varies from 30m for coarse resolution to 1m for fine Cannot exceed the limits of the sampling LIDAR derived DEM has a cell size of 1 m2, and vertical error of 15 cm2

To work with DEMs in Civil 3D, follow directions for Example 1.

These files are imported with metric units for elevations. They must be converted to feet using ARCMAP

LAS point cloud .laz

ftp.lidar.dnr.state.mn.us

Contains a variety of point information 1. Number of returns 2. Return number 3. Intensity 4. X,y,z values 5. Scan direction 6. Classification

LIDAR point classification are as follows: 0 – created, never classified 1 – unclassified 2 – ground 3 – low vegetation 4 – medium vegetation 5 – high vegetation 6 – buildings 7 – low point (noise) 8 – model key-point 9 – water 10 – reserved 11 – reserved 12 – overlap Most often used points for Civil 3D are category 0 and 2. LASTOOLS required to process the LAZ data

Data from the ftp site is in .laz format. See LAZ handout for directions on working with LAZ files: ftp://lidar.dnr.state.mn.us/tools/lastools/LAS_File_Processing_Using_LASTOOLS.pdf See handout for string to type in when setting up LAS output: las2txt –i <file name.laz> -o <file name.txt> -parse xyz –sep comma – keep_class 2 8 – scale_x 3.280839895 –scale_y 3.280839895 – scale_z 3.280839895 Note: When entering this chain, do not include the “<” and “>” before and after the file names Benefits of using LAZ files are:

1. More points come in with LAZ files 2. The points are on a 1 meter grid 3. Points are higher density

LAS files can be converted to Shapefiles and ASCI files LAS files can be used to generate DEMs LAS files can be exported to a .txt file


Shape files .shp

Red River Valley web site DNR LRP site

May need to convert to feet elevations. To do that, you will need to manipulate the file in ARCGIS as follows: Must have .shp, .shz and .dbf files to work Good for use with quick watershed maps Come into civil 3D as contours Fast and easy to import

Gdb files are only available on the southern part of the state. To get a .shp file, it must be converted in ArcMAP Note: .shp files are available off the Red River Basin website, which are emailed to you. Those are in metric, which must be converted through Mapconnect.

Google earth data

www.earth.google.com

Data was collected in February 2000 by space shuttle Endeavor. Data is not updated on a large scale. Vertical accuracy of 16m.

Get data from “Earth Gallery” under the Layers files selection Select “Terrain and Elevation” Only some data is available; select areas by trial and error


Managing Data

Programs and software to manipulate data includes:

ARC GIS

LAS readers

See separate handout on “LAS Files Processing using LASTOOLS”. This is accessed online at

ftp://lidar.dnr.state.mn.us/documentation/LAS_File_Processing_Using_LASTOOLS.pdf

Use this chain to convert data:

las2txt –i <file name.laz> -o <file name.txt> -parse xyz –sep comma – keep_class 2 8 – scale_x 3.280839895 –scale_y 3.280839895 – scale_z 3.280839895

Note: Do not include the “<” and “>” before and after the file names

Stand-alone viewers (free)

o Qcoherent (www.qcoherrent.com)

o Fugro EarthData (www.fugroviewer.com)

o Sanborn( www.sandborn.com/technologies/lidar.asp)


CREATING SURFACES

The main goal in working with any LIDAR data is to create a surface with the LIDAR data, regardless of the type. Bringing in a point cloud may prove cumbersome, and not needed if the surface can be generated instead. Surfaces are created in Civil 3D using the “Surfaces” menu in the “Create Ground Data” panel. Or, surfaces can be created using the Prospector, by right clicking on the surface line under each project. Examples of each are included in the exercises at the end of these notes:

Exercise County Description 1 Nicollet Use .dem data in design 2a Chippewa Use .shp file data to build a surface 2b Chippewa Using a .gdb file to create a shape file 3 Chippewa Importing a DEM with .adf files and creating a surface 4 Chippewa Using .las data to build a surface Surface tools: Finding spot elevations Find “Annotate” tab Then, “add labels”, select “Surface” then “spot elevation” Select the point to label…this creates an actual label as a text object Creating a “quick profile” Find the “Analyze” tab Select “quick profile” from the “Ground Data” panel Select two points and then select the lower left hand corner for drawing the profile Using Waterdrop Select the surface Find “Waterdrop” under the “Analyze” panel Select a point on the map….watch where the water will go Slope arrows Slope arrows can be used to determine drainage direction. To change the display,

1. Select the surface name and right click, select “surface properties” 2. Under “surface style”, select the draw down next to the name, and select “copy current

selection” 3. Under information, change the name to “slope analysis” 4. Change the display and slope options as directed in class.


EDITING SURFACES

Surface data can be very large and cumbersome. To eliminate some of the points, you may choose to do some of the following. Note that any edits made to a surface will show up in the “definitions” tab under “Surface properties”. Any edits that you do not want can simply be deleted here. Edits can also be moved up or down in hierarchy using the arrow keys. The most basic steps in making a better surface model are in the Surface Properties dialog. Manual surface edits The commands below can be used once a surface is built. They are used to subjectively edit the data or the surface TIN elements. All are accessed from the “Surface” tab, then selecting “Edit Surface” tab, or by selecting the surface itself.

1. Add line 2. Delete line 3. Swap edge 4. Add point 5. Delete point 6. Modify or move point

Note: move point will only move horizontally; modify will move in all directions 7. Minimize flat areas

Note: this will create a more accurate surface, forcing triangulation to work in the z direction instead of create flat planes

8. Raise/lower surface 9. Smooth surface

NNI: This adds points to the surface on the basis of a weighted average of nearby points. Kriging: This adds points to the surface based on one of five different algorithms.

10. Paste This will replace the data on a surface with data from a new surface. Remember to paste a smaller surface into a bigger surface, and the newer surface into the older surface. The surface being pasted onto will be overwritten.

11. Simplify surface This option is useful in LIDAR applications, as it allows the user to reduce the number of points used in the surface itself. To simplify: Expand the Surface Name all the way down to “Definition” Right click on the “Edits” option, and select “Simplify Surface”


Select the “Point removal” option, and then, “Next”

Keep the button selected for “Use existing border” and select “Next”.


At this screen, determine what percentage of points to remove and the maximum change in elevation desired. This value is the maximum change allowed between the surface elevation at any point before or after the simplify process has run. Click apply and then “finish”.

Editing surface properties

1. Expand the Surfaces branch 2. Right click the surface name and select “Surface Properties” 3. Select the definition tab. 4. Under Definitions Option at the top of the dialog, expand “Build”

Under the Build option you can: Copy deleted Dependent object When you select “Yes” and an object that is part of a surface definition is deleted, the information derived from that object is copied into the surface definition. Setting this option to “True” in the surface properties will let you erase polylines from the drawing file, while still maintaining the surface information.


Exclude elevations less than Setting this to “Yes” puts a floor on your surface. Any point less than this value will not be included. Exclude elevations greater than This puts a ceiling value on your surface. Use Maximum triangle length This limits the number of narrow triangles drawn at the border of the site. Adding to a surface:

1. Select the surface to initiate the surface editing commands 2. Find “Add Data” in the “Modify” panel 3. Here you can add a DEM file, point file, or other data sources


Data clipping a surface: This can be done a variety of ways. One easy way is to “add a boundary” to the surface. This is done as follows:

1. First, draw a polyline that defines the area you want to “clip” on the surface 2. In Prospector, expand the surface name, all the way down to “definitions” option 3. Right click over “boundaries” and select “add” 4. Now, select the polyline you drew earlier to clip the surface.


Adding breaklines: Adding breaklines is done in the same way as adding a boundary.

1. First, draw a line that defines the breakline you want to add (or identify the breakline from survey data)

2. In Prospector, expand the surface name, all the way down to “definitions” option 3. Right click over “breakline” and select “add” 4. Now, select the polyline you drew earlier. 5. The breakline has been added, and the surface should reflect that breakline addition

Cropping a surface: This is a different option than “surface clipping”. When cropping, a whole new surface is created, which can be useful when dealing with large data files.

1. Expand the Surface Tools drop down and select “Create cropped surface” 2. Specify a name for the cropped surface. 3. Select the ellipse next to the “select crop area” option, and type in “O” to specify an

object 4. Select the polyline you created to border the new cropped area 5. Select inside the polyline when prompted for a point. The polyline will now be

highlighted. 6. In Drawing for a New Surface option, select “create a new drawing” 7. Under “New surface name”, enter a new name 8. Then, select “create a new drawing” and pick the civil Imperial template file

Once in the new drawing, type “Zoom”, then “Extents” to see the new surface:


Exercise 1: Using DEM data in design This project involves the design of a drainage channel and outlet structure in Nicollet county. The DEM files were obtained from the DNR data deli website (at www.lidar.state.mn.us) and then manipulated using ARCGIS. Directions for the design project are as follows: Part 1: Importing a DEM with .adf files and creating a surface 1. Open Civil 3D and create the new drawing and project entitled “Exercise 1 DEM county

drainage structure.dwg”. Use the Autocad Civil 3D imperial template file. 2. All of the files you need are on the flashdrive in your computer, under the “Exercise 1”

folder.

3. First, connect to the background tile for Nicollet County:

Command: MAPCONNECT Select: the Nicollet county.sid file located in the “Exercise 1” folder Click on “Add to Map” Put the photo on a separate layer called “PHOTO”, so that it can be frozen to speed regeneration and drafting time. Put this photo on its own layer (suggested name: “Photo”) so that the layer can be frozen to speed regeneration time.

4. Next, bring in the point file from the MN DNR website:

From the Prospector, right click on “point cloud” and then “create point cloud”. Accept the default name or enter another (click “next”) For data, choose “ESRI ADF” data file Populate the file screen with ALL THE FILES in the “dem” folder, under “Exercise 1”


Now, your computer will give you a message that it is creating the point cloud. This will take a while. When the point cloud is complete, change its name as follows: Right click on Point Cloud (1) under the Prospector tab. Select the top line “Point cloud properties”, then click on the point cloud name. Change it to “LIDAR DATA” Note: you can change the properties of the point cloud display as follows: In Prospector: Right click on the point cloud name, then select “edit point cloud properties” Under the “display” tab, turn off the bounding box and points display options:


5. Next, create the surface:

Right click on the point cloud listed in the Prospector, under “point cloud” and select “Add points to surface”. Select the type of contours you want to show (1’ and 5’ background) Again, this will take a while. When the surface is created, contours will appear.

6. To change the appearance of the point cloud, right click on its name in the Prospector tab, then, select “point cloud properties”. Select “no display” under the heading “Point cloud style” which is on the “Information” tab. Other ways to change the display are discussed in class.

7. To change the contour appearance, go into the Prospector and selecting the surface name,

then right click and select “Surface Properties”.


NOTE: You can also create the surface directly from the DEM. *** Which is better? Discuss! To do that: In the Home tab, find “Create Ground Data” panel. Select “Create surface from DEM” In the Grid surface from DEM dialog box, find the .dem, or .adf file. Click “open” This will accomplish the same thing as the above. Part 2: Design 8. First, determine a proposed centerline for the berm structure.

Create a layer called “berm structure” and make it current. In the “project area” identified by the instructor, find a suitable area to place a berm structure and outlet. Create an alignment for the structure as follows: Using the “create line” command on the Draw panel, create a line indicating one or more portions of the berm. Then, use “create curve between two lines” to round out the corner. Create the curve using the “radius “ option and select a radius that fits the berm layout.

9. Define this centerline as an alignment as follows:

In the “create design” panel, select “Alignment”, then “create alignment from objects” When prompted, select the line or line, curve and line that make up your berm structure centerline. When prompted for stationing direction, accept the proposed or reverse it. Determine a beginning stationing for your berm structure and enter it as shown:


10. Now, create the alignment for the outlet channel:

Create a layer called “outlet structure” and make it current. Near the berm, find a suitable area to place the outlet channel. Create an alignment for the outlet structure as follows: Using the “create line” command on the Draw panel, create a line indicating one or more portions of the outlet channel. Then, use “create curve between two lines” to round out the corner.

Create the curve using the “radius “ option and select a radius that fits the outlet channel layout. 11. Define this centerline as an alignment as follows:

In the “create design” panel, select “Alignment”, then “create alignment from objects” When prompted, select the line or line, curve and line that make up your outlet channel centerline. When prompted for stationing direction, accept the proposed or reverse it. Determine a beginning stationing for your outlet channel and enter it as before.

12. To create a profile for your berm structure and outlet channel:

Select “Create design” tab and find “Profile” and then, “Create Surface Profile” Select the berm structure as the alignment you want to work with.


Accept the profile default name select the “ADD” button in the lower right hand corner Click on the “Draw in Profile View” button To name your profile view, click on the icon to the right of the “Profile view name” field, and in the box for “property fields” select “parent alignment” Now, select “create profile view” and select the point where you want the LOWER LEFT HAND CORNER to be for the profile graph. LEAVE room for the profile, and if you need to move it, use the correct command.

13. Now, create the finished ground profile

First, draw all of the TANGENTS for your proposed profile using simple AutoCAD Line draw and the Transparent Command Bar (located on the right edge of your screen). This allows you to draw a line by typical Autocad methods, or by station and elevation, or by station and grade. Once the tangents are complete, use the “create design” tab and find “profile” then “profile creation tools”. Select the grid for the profile you wish to work on when asked to select a profile view. Give the profile a “name” and accept the default layers. Once that is done, the “profile creation tools” toolbar will appear in graphics space. This can be accessed again in one of two ways: 1. By selecting your profile and then the “profile geometry editor”

2. By selecting your profile and then right click over it, find “edit profile geometry”

To develop the finished ground profile, use the tangent and curve buttons on the far left side of the toolbar. You can also use the “transparent” commands that are on the right edge of the graphics space. These allow you to specify the station, elevation, or grade from one point on the profile to another. Note: when you are done creating the profile, you can finalize it by escaping out of the profile creation command prompt. If you are not done, you can edit the profile using the grips or by using the profile geometry editors.


Note: if you lose the Transparent Commands toolbar, you get it back by: View Windows Toolbars Select “civil transparent” To label any point on the profiles: First set up the station offset label style for “profile views”: Then, select “Annotate” and then, “Add labels”. Select “Profile view” labels, and the label type is “station offset”. Specify the station to label and the elevation, and you can drag the label anywhere on the profile view. 14. To create the sections and surface for the new embankment channel

Reference the typical section in your notes. Civil 3D calls a typical section an “assembly” and the elements of each are called a “subassembly”. Step one: create a main assembly. In the Home tab, select “Create Assembly” from the “Create Design” tab Select an insertion point anywhere on the screen Now add the subassemblies:

1. You can either select one that is already complete, or make your own. To select one that is complete, choose from the “assembly” tab on the Subassembly palette.

2. You can create your own subassembly as follows:

Select from the list of objects the subassemblies that you want. For this project we will need:

● Shape Trapezoidal ● Basic cut slope Insert each element and change the properties of each to match the typical section provided. Rename this assembly “embankment assembly”

Now you can copy that “embankment assembly” and use it for the other types of assemblies you need. To do that, just use an Autocad commands.


For this assignment, we can also create a subassembly for the embankment channel. Typically, the spillway will be cut 0.5 foot into natural ground, and placed on the edge of the embankment. Note that an assembly has three elements: Points (P), Links (L), and Shapes. A point represents where an assembly connects to another object, a link is a surface that connects two points, and a shape represents a closed polyline and is used to determine quantities.

15. To create a corridor A corridor is a 3D model of our alignment. We will create two corridors for this project. A corridor is a combination of a horizontal alignment (a baseline), a profile, and an assembly. To create a corridor:

1. From the home tab, select “corridor” then “create simple corridor” 2. You will need to specify one baseline, one profile, and one assembly 3. Name the corridor 4. Specify the layer that it goes onto

Select the baseline by left clicking on it: then, select profile Now, a dialog box will pop up that asks you to specify the target surface to connect the slopes to. Do this by clicking on “Surfaces” and then selecting “surface 1”, or whatever the LIDAR surface is called in this drawing (note the “click here to select all” option”) Note now that the corridor is built. Remove all sections that go through an intersection by selecting the corridor (left click on it) and then right click and select “corridor properties” Also note that here you can change the frequency of application of each assembly. For example, through a curved section, you can change the frequency to 10’.


Exercise 2: Using Shape file data to build a surface

All of the files you need are on the flashdrive in your computer, under the “Exercise 2” folder. There are at least two ways to convert .shp files: both require ArcMAP: Method 1. Use ArcMAP to convert the contour files to a .dwg file.

1. First, the .shp file must be converted to feet units as follows:

2. Open a new (blank) ArcMap document, set the data frame coordinate system to UTM 15N

3. Through the ArcCatalog extension found in ArcMap, navigate to the folder that contains the files.

a. You should see one file available with the file extension “.shp” and you can drag and drop this file on to the map

b. This data can also be added by using the add data button (black plus on top of yellow squares). Navigate to the folder again and select the “.shp” file to add.

4. With the contours added to the map, add a basemap to check the location of the contours has been added properly (which basemap doesn’t matter).

5. Then either use the “information” button or open the “Attributes table” to view elevations and to ensure they have come in properly.

6. After ensuring that all data has been added correctly, right click on the contours in the “Table of Contents” and go to “Data” then “Export to CAD”

7. Then set your folder destination where the DWG should be saved and select the version of CAD you wish to save in (2004, 2007, 2010, etc.).

8. When the DWG is finished generating it will appear on your ArcMap and should fall right on top of your current shapefile in ArcMap.

9. You can then open the DWG separately in an AutoCAD application. This process will generate 3D contour lines. The elevation becomes embedded in to the file when you export it out of ArcMap. 1. Now, in Civil 3D, open the “Chippewa contour elevations” drawing. 2. Create a new surface:

In prospector, right click over the surfaces, and select “Create Surface” You can rename the surface, if you’d like, by right clicking over the name and selecting “edit surface properties”, then highlight over the name and change it. Now, add data to the surface, by expanding it (double click on the name) and then expanding the “definition” menu. Select the “contours” option and then right click over it to find “Add”.

Then, click and drag over all the contours that were brought in with the .shp file.

Proceed with design now that you have the surface data. Note, since this .dwg file was created in ArcMAP, there are no pre-set layers or styles.


Method 2: Create .shp files from the .gdb files in ArcMAP In ArcMAP drag the .gdb file and export the contours as a .shp file. Create a new drawing called “Exercise 2 chippewa.dwg” Import the .shp files as follows: MAPCONNECT Select the chippewa.shp files that are in the exercise 2 folder Select “Add to map” Follow the directions that are given in the attached handout entitled, “Inserting Shapefiles using Create Surface from GIS data” Discussion Question: Are people having trouble with .shp files coming in with “0” elevations?


Exercise 3: Working with a geodatabase to build a surface

This project is also in Chippewa County. Part 1: Importing a DEM with .adf files and creating a surface The DEM files were obtained from the DNR data deli website (at www.lidar.state.mn.us) and then manipulated using ARCGIS.

1. Open Civil 3D and create the new drawing and project entitled “Exercise 3 chippewa county project.dwg”. Use the Autocad Civil 3D imperial template file. All of the files you need are on the flashdrive in your computer, under the “Exercise 3” folder.

2. Connect to the background tile for Chippewa County:

Command: MAPCONNECT Select: the Chippewa county.sid file located in the “Exercise 3” folder Click on “Add to Map” Put the photo on a separate layer called “PHOTO”, so that it can be frozen to speed regeneration and drafting time. OR, open MAPWSPACE and connect through the WMS site: http://geoint.lmic.state.mn.us/cgi-bin/wms?

3. Bring in the point file from the MN DNR website: From the Prospector, right click on “point cloud” and then “create point cloud”. Accept the default name or enter another (click “next”) For data, choose “ESRI ADF” data file Populate the file screen with ALL THE FILES in the “dem” folder, under “Exercise 3”


Now, your computer will give you a message that it is creating the point cloud. This will take a while. When the point cloud is complete, change its name as follows: Right click on Point Cloud (1) under the Prospector tab. Select the top line “Point cloud properties”, then click on the point cloud name. Change it to “LIDAR DATA” Note: you can change the properties of the point cloud display as follows: In Prospector: Right click on the point cloud name, then select “edit point cloud properties” Under the “display” tab, turn off the bounding box and points display options:


4. Next, create the surface: Right click on the point cloud listed in the Prospector, under “point cloud” and select “Add points to surface”. Select the type of contours you want to show (1’ and 5’ background) Again, this will take a while. When the surface is created, contours will appear.

5. To change the appearance of the point cloud, right click on its name in the

Prospector tab, then, select “point cloud properties”. Select “no display” under the heading “Point cloud style” which is on the “Information” tab. Other ways to change the display are discussed in class.

6. To change the contour appearance, go into the Prospector and selecting the surface name, then right click and select “Surface Properties”.

Part 2: Design Find the existing drainage channel in the southern portion of the surface. Now, use AutoCAD line draw commands to create the alignment. Draw the lines on top of the photo, after creating a layer called “channel”. Estimate the radius of the curves, and use the “curve between two lines” command to generate the alignment.


1. Create an alignment as follows:

In the “create design” panel, select “Alignment”, then “create alignment from objects” When prompted, select the line or line, curve and line that make up your outlet channel centerline. When prompted for stationing direction, accept the proposed or reverse it. Determine a beginning stationing for your outlet channel and enter it as before.

2. To create a profile of this channel:

Select “Create design” tab and find “Profile” and then, “Create Surface Profile” Select the “channel” as the alignment you want to work with. Accept the profile default name select the “ADD” button in the lower right hand corner Click on the “Draw in Profile View” button To name your profile view, click on the icon to the right of the “Profile view name” field, and in the box for “property fields” select “parent alignment” Now, select “create profile view” and select the point where you want the LOWER LEFT HAND CORNER to be for the profile graph. LEAVE room for the profile, and if you need to move it, use the correct command.


Exercise 4: Using LAS files to build a surface

This project is also in Chippewa County. The laz file is downloaded from the lmic website. Then, they are run through the lastools.exe program (select las2txt.exe). The directory is changed and the following string is input. We will email this to you, and it is included as a separate document in your notes.

The elevations of these points can be edited by exporting them in the .txt file. Note the final format. The points are input as follows: Create ground data Create point cloud

Select any point cloud format that is x, y, z with comma delimited (or space delimited if you transferred them to an excel spreadsheet) Navigate to the output file you specified in LASTOOLs and change the coordinate system


Specify the coordinate system: UTM83-15F

You will have to wait as the point cloud is created. Once the point cloud is created, you can add it to the surface.

Version date:Sept 2012

civil 3d point and surface

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