Adjustment of Traverses in GeoSurvey

Written By Peter Poole, Monteath & Powys, Newcastle.

There are two types of adjustments that can be undertaken in GeoSurvey.
Procedure
  1. Open GeoSurvey
  2. Create a new job.
    For demonstration purposes, create a job with your name in E:\Training\Training Module No.1 Adjustment of Traverses\Training Exercises
  3. Click on Points Mode
  4. Insert the coordinates of a known point in your traverse (Important)
    i.e. Point 1 , 200E, 500N (See diagram)
  5. Click on Strings menu on Tool Bar
  6. Click on Traverse/Parcel
  7. Click on Add Traverse, Give your Traverse a name eg "Traverse" 1 or "Main Traverse" and
  8. Click on Edit
  9. Enter your traverse with the first known station in the "From" column
    i.e. Point 1(point number you entered in step (4)
  10. Enter bearings and distances clockwise from Point 1 (Stn 1)


  11. For a loop traverse, make sure that you enter the correct station numbers. Use the [enter] button not the [tab] button once you have typed the value
  12. The program will automatically put in its own station numbers but you can type over these with your station numbers.
  13. Make sure closing station number , in this case Point 7 is changed to the starting point number being 1
  14. To access the functions of the editing window you right click the mouse button to get a floating menu.
  15. At this stage you can check your misclose by clicking [Calc misclose].



  16. Print the initial misclose in your list file .lst by right clicking the mouse for the floating menu and choose "Print Traverse" .
    Enter file name to create a List file ".lst" ie. .lst in the folder E:\Training\Training Module No.1 Adjustment of Traverses\Training Exercises
    Parcel "Main Traverse/"    15-Mar-2012 15:53:58
    Original Dimensions Shown
    From      Bearing   Distance      Pt      Easting     Northing     Radius    ArcDist
                                       1      200.000      500.000                      
         1  178 54 21    122.548       2      202.340      377.474                      
         2  267 51 30    110.645       3       91.772      373.339                      
         3    2 00 37    131.941       4       96.401      505.199                      
         4    4 17 30     68.918       5      101.558      573.924                      
         5   89 59 58     98.435       6      199.993      573.925                      
         6  179 59 55     73.923       1      200.000      500.000                      
    Misclose  11132'14"    0.005m    Acc: 1/111241
    
  17. Make sure it is saved in the Current Survey directory and that you select when requested to amend or replace.
  18. At this stage depending on your angular close which has been determined by your field readings you may want to adjust the bearings before you run the Bowditch adjustment. In our example you have a misclose of only 5"
  19. In your calc book, paste in two copies of the initial misclose.



  20. On the second copy adjust your bearings by writing the adjusted bearings in pen.
  21. In the edit traverse window you can now overwrite the bearings with your adjusted bearings, Right click and [Calc Misclose] again
  22. Print Traverse again. Use the "Append" option and not "Replace" when printing and paste in your calc book. Hopefully your misclose has been decreased. Do NOT tick the "Print Adjusted Dimensions Box"
  23. Now it is time to apply the Bowditch adjustment by Right Click and choose the option
  24. Note the the bearings and distances displayed, your raw traverse remain displayed unchanged however adjusted points have been written to the main file and show on the main screen.
  25. To print the adjusted bearings and distances right click and tick the "Print Adjusted Dimensions box". Print, Append and Paste in Calc book.
  26. Close the edit Traverse screen and return to main screen.
  27. Here you will find your loop traverse adjusted and joined by a traverse string.
  28. If you require a certain traverse line orientated to a fixed starting azimuth ie "X"-"Y", you can rotate around your initial known point. In this case swing your job +0?00'02" around Point 1
  29. Select on the Tool Bar
  30. Select
  31. Select , the default is All Points, All Layers which is fine if you have only traverse points in your file. If you have other existing points in the file you will have to select the range of new traverse points.
  32. Select tick box
  33. Key in the rotation angle +0?.00'02"
  34. Key in rotation point, Point 1
  35. Select
  36. Check that you have rotated your traverse correctly so the "X-Y" starting azimuth in our case is 0?00'00"
  37. To adjust a traverse between two fixed points, you must key in the two fixed points in your job before you start and proceed as above.