Mapping Tutorial by HC120831083637

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									Fall 2004                                CIV.E 125/ENV. E. 100                                              43
                                      Preparation of a Baseline Map


                CIV.E. 125 - Civil Engineering Concepts
            ENV.E. 100 - Environmental Engineering Concepts

                                             AutoCAD

                Tutorial #3 - Preparation of a Baseline Map

Overview:        The purpose of this tutorial package is to allow each student to begin construction of a
                 map illustrating the surveyed details at the Columbia Lake site.

                 The map will illustrate the location of your project baseline and the approximate location
                 of the surveyed benchmark.

Concepts:        DDINSERT
                 BLOCK
                 MOVE
                 DTEXT
                 DDEDIT

Instructor:      Bob McKillop
                 E2-2302
                 ext. 6372

1.0     Web Site Downloads
Before you begin your next drawing, you need to access the course web site using your web browser once
again.

If you have been following instructions, you should have a subfolder called Survey_features on your
personal disk space. If you don’t, create one with the following file structure:


You will need a subfolder            N:\ CIVE125
to hold your survey                         AutoCad_files
drawings.                                          Survey_features
                             or

                                     N:\ ENVE100
                                            AutoCad_files
                                                   Survey_features


In order to save you time, a series of AutoCAD drawings are provided for you on the course web site.
These addition drawings provide the default symbols for your benchmarks, hubs, trees, etc.

You will incorporate these drawings into your drawings by treating these drawings as blocks. In
AutoCAD, blocks are a very powerful feature. More on blocks later….
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                                        Preparation of a Baseline Map

The procedure for inserting these files into your drawings will be provided later in this tutorial.


Download the following                  1)       hub.dwg
files from the web site and             2)       tree.dwg
save them to your                       3)       bench.dwg
Survey_features                         4)       elev.dwg
subfolder                               5)       bm.dwg
                                        6)       xsect.dwg
                                        7)       interestpoint.dwg



Exit your web browser and start up the AutoCAD program if you have not already done so.

2.0      Starting AutoCAD
Begin this tutorial by loading your Location Map created previously.


Re-name your drawing          Using the “Save-As” command, save the AutoCAD drawing as
                              “baseline_map.dwg” in the following folder:

                                        N:\ CIVE125
                                               AutoCAD_files
                                                     Survey_features/baseline_map.dwg
                              or

                                        N:\ ENVE100
                                               AutoCAD_files
                                                     Survey_features/baseline_map.dwg


2.1     Fixing the Title Block Text
Now is a convenient time to fix our title block. Several of the current title block text entries apply to our
Location Map title block and are obviously incorrect for our Baseline Map.


Turn off a drawing layer      Use the LAYER command to turn off the layer called
                              2004_location_map_text.



Change your title block       Use the layer command to set the layer called 2004_border_text as the
entries                       current layer.

                              Using the DDEDIT command, change the following text items:

                                        1)       Date:                   to today’s date
                                        2)       Map Title               to “Surveyed Baseline”
                                        3)       Drawing Number          to 2004-02
                                        4)       Scale                   just leave this text blank for now.
                                                                         You will determine the best viewing
                                                                         scale for your specific survey at the
                                                                         end of the tutorial.
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                                     Preparation of a Baseline Map

Save your work.

3.0      Creating Your Baseline Map
3.1      Indicating Your Benchmark on your Map
Now you can begin to work on your new drawing. We now need to zoom in on our drawing in the vicinity
of the project benchmark and Hub #1.


Work in model space         Click on the Model tab at the bottom of your drawing to begin working in
                            model space.



Use the ZOOM command        On the command line type z (for ZOOM) and press the <enter> key.
to view your site.
                            Press w (for Window) and press the <enter> key. You will be asked to
                            specify the first corner of your new viewing window. Locate your mouse
                            pointer near the location of your project benchmark and left click your mouse.

                            Locate the other corner of your window and left click your mouse once again.

                            Whenever you want to ZOOM back out, simply press z (for ZOOM) and e
                            (for EXTENTS).


Your drawing should appear similar to the following with your survey site located somewhere on the
display.
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                                     Preparation of a Baseline Map

For this tutorial, we will adopt one of the benchmarks located near Columbia Lake and demonstrate how to
locate a leg along a hypothetical traverse. Each group should examine the example presented in these
notes but should work with their own actual survey data.


Change the current layer    Your drawing should contain 2 drawing layers called Civil_baseline and
                            Civil_baseline_txt.

                            Change the current layer to “Civil_baseline”.



Locate your assigned        On the command line, type DDINSERT to display an “insert” dialogue box.
benchmark on your
drawing.                    Click on the “Browse…” command button and open the file called
                            “Bm.dwg” from your AutoCAD/Survey_features folder.

                            Click on the Insertion point and Scale option buttons in order to have
                            AutoCAD allow us to specify those parameters on screen one at a time. Do
                            not click the Rotation buttons. Do not explode the drawing. Click the OK
                            button.




You will be prompted for    1)       an insertion point.       On your drawing, specify the (x,y)
a number of items:                                             coordinates of your benchmark and left
                                                               click your mouse. The coordinates of all
                                                               benchmarks are available on the course
                                                               web site.
                            2)       X scale factor            Specify a value of 1 or 2. Adjust the scale
                                                               factor to suit your individual drawing.
                            3)       Y scale factor            press <enter> to accept the default (the X
                                                               scale)
                            4)       Bench mark name           type in your project benchmark number
                                                               (i.e. BM-1)
                            5)       Bench mark elevation      type in the appropriate bench mark
                                                               elevation (i.e. 334.814)

                            Your drawing should now display your benchmark block drawing in the
                            correct location.
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                                      Preparation of a Baseline Map

Following our hypothetical survey, a benchmark symbol should now be displayed on your drawing.




3.2     Locating Hub #1 on your Map

We will now use another block called “Hub” to identify the stations defining the baseline of your survey.

                             On the command line, type DDINSERT to display an “insert” dialogue box.
Locate your assigned
Hub #1                       Click on the “Browse…” command button and select the file called
                             “Hub.dwg” from your AutoCAD/Survey_features folder.

                             Click on the Insertion point and Scale option buttons in order to have
                             AutoCAD allow us to specify those parameters on screen one at a time. Do
                             not click the Rotation buttons.

                             Do not explode the drawing.


                             Click the OK button.
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                                    Preparation of a Baseline Map



Again, you will be         1)       an insertion point.       Using the total station, Terry Ridgway
prompted for a number of                                      identified the AutoCAD coordinates for
items:                                                        Hub #1 of your baseline.

                                                              The coordinates of your Hub #1 are
                                                              listed on the course web site.

                                                              At the prompt, specify in the coordinates
                                                              of your hub.


                           Also enter the following information when prompted:

                           2)       X scale factor            Specify a value of 1 or 2 (adjust if
                                                              necessary)
                           3)       Y scale factor            press <enter> to accept the default (the X
                                                              scale)
                           4)       Station elevation         type in the appropriate hub elevation (i.e.
                                                              334.520)
                           5)       Station name              type in your first traverse station
                                                              (i.e. Hub #1)


Your drawing should now contain the inserted benchmark symbol and your specified elevation and hub
identification similar to the example shown below.
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                                          Preparation of a Baseline Map


3.3      Drawing the First Leg of your Baseline

We will now draw the first leg of our hypothetical traverse as part of this tutorial.

         For the purposes of illustration, we will adopt a leg 25.55 metres in length, following a
         bearing of N6522’00”E. Each group should use their respective field data.


Draw your first traverse      On the command line, type LINE and press the <enter> key.
leg
                              You will be prompted with “From Point:” Type “int of” to indicate that you
                              want AutoCAD to snap your line endpoint on the intersection of the lines that
                              you indicate. Now, locate your cursor on the centre of Hub #1. Your screen
                              display should provide a pickbox at the intersection of the two lines defining
                              the Hub symbol. Left click your mouse.

                              The command line will display “To point:”, prompting you for the other end
                              of the line. In our case, the other end of the line is Hub #2.

                              On the command line, following this tutorial example, enter the following:

                              To point:           @25.55<n65d22'00"E         followed by pressing <enter>
                                                                             twice.


Your drawing would now display the first leg of your traverse similar to the example shown below.
Fall 2004                              CIV.E 125/ENV. E. 100                                         50
                                    Preparation of a Baseline Map



Place Hub #2 on the end    On the command line, type DDINSERT to display an “insert” dialogue box.
of the line representing   Click on the drop down arrow button and select the block called “hub”. Click
Leg #1 of the baseline.    the OK button. Do not explode the drawing.

                           Again, you will be prompted for a number of items:

                           1)       an insertion point.      On the command line type “end of” to tell
                                                             AutoCAD that you want to locate the Hub
                                                             symbol at the end point of the line. On
                                                             your drawing, locate your mouse pointer
                                                             at the end of the line and left click your
                                                             mouse.
                           2)       X scale factor           Specify a value of 1 or 2
                           3)       Y scale factor           press <enter> to accept the default (the X
                                                             scale)
                           4)       Station elevation        type in the appropriate hub elevation (i.e.
                                                             334.998)
                           5)       Station name             type in your first traverse station
                                                             (i.e. Hub #2).


Your drawing would now look like the following:
Fall 2004                                CIV.E 125/ENV. E. 100                                            51
                                      Preparation of a Baseline Map



Change the current layer     Using the LAYER command, change the current layer to
                             “Civil_baseline_txt”.



Enter any text identifying   On the command line, invoke the DTEXT command. You will be prompted
the traverse leg             for the start point. On the command line, type “int of” and click on the centre
                             of Hub #1.

                             Specify a text height of 2 mm (or a size appropriate to your drawing)

                             When prompted for the rotation angle, type “int of “ and click on the centre of
                             Hub #2.

                             When prompted for the text, type in the bearing of the leg. (Note: in
                             AutoCAD, %%d displays the “degrees” () symbol).

                             Text:    type N65%%d22’00”E                  and press <enter> twice.

                             The text will now be positioned on the line representing the leg. We need to
                             move the text entity to a more desired position.



Move the text string.        On the command line, invoke the MOVE command. When prompted, select
                             the text and move to a better location, centred between the hubs and off the
                             traverse line, as shown below.
Fall 2004                                 CIV.E 125/ENV. E. 100                                               52
                                       Preparation of a Baseline Map


Repeat the entire process to display the length of the leg (i.e. 25.55 m) beneath the line as shown below:




3.4      Completing the Construction of Your Baseline

Save your work.

Your hub symbols should be located on the civil_hub layer while your hub text entries should exist on the
civil_hub_txt layer. Your traverse leg should be drawn on the civil_baseline layer and the baseline text
(bearing and length of leg) should now be located on the civil_baseline_txt layer.

Each project group should now be able to repeat the process outlined in Section 3.3 in order to draw the
entire traverse (i.e. Hubs 3 and 4) defining the baseline of the field survey.

4.0      Examining Your Constructed Baseline

On the command line type z (a shortcut for ZOOM) and press the <enter> key. Type e (a shortcut for
EXTENTS) and press the <enter> key. If needed, use the Zoom (z) and Window (w) commands to zoom
in on your baseline. Use the PAN command to adjust your screen display.

Examine your baseline. If your baseline looks incorrect (i.e., one of your hubs is located in the middle of
the lake!!) you need to re-examine your field book and spreadsheet calculations for errors.

5.0      Display at a suitable scale

Finally, use the Zoom command to view your baseline map at a suitable plotting scale (i.e. 1:1000 or
something similar). If you do not understand scaling, refer back to tutorial #2. Return to paper space and
specify the scale in your title block. Print a hardcopy for your report.

Save your work one last time.

								
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