Land Surveyor Forum

Replies

• 

  Ivan March 23, 2013 at 6:38pm

  Hey,

  If you want to establish the vertical and rectangular accuracy fo that buildings, you have to find the control points used to build those structures, then start collecting asbuilt info to compare what is built vs what was projected.
  • 

    Sarfraz Ahmed > Ivan March 26, 2013 at 3:57pm

    as mentioned by john earlier you set up the instrument and you could check the deviation in structure but you cant explain it to your engineer unless you convert the angular difference in to linear measurement.

    you must need to know this inside out...

    both systems grad & degrees are explained below

    unit Gon (400)

    1 gon                  =                 1m per 63 m

    0.001 gon          =                 1 mm per 63 m

    Unit degrees (360 degrees , decimal)

    1 degree            =                 1 m per 57 m

    0.001 degree     =                 0.001 mm per 57 m

    Remember

    Read it like m, dm, cm or mm per 63 or 57 m

    you can now apply Pythagorean theorem to determine the value...  

    check object distance with reflector less or with prism.

    tan(angular difference) *dis= ans

    e.g:  difference was 25" in decimal 0.0069

    and distance is 50 m

    tan 0.0069*50=0.0060m

    HOPE THIS WILL HELP
    • Land Surveyor

      RAYMOND KINGSLY > Sarfraz Ahmed June 13, 2016 at 7:58am

      CORRECT..............
• 

  john March 21, 2013 at 5:50am

  thank you jazu. the degree of verticality will depend on the structural design and loading of the building among other many factors such as the height. This should be provided by the structural engineer in charge. so you can tell him to give you the error allowed as per his structural design. I hope I have answered you. What i know is that there are complex structural calculations involving loadings that Geomatic engineers have to consult from other engineers.
  • 

    jazu > john March 21, 2013 at 4:47pm

    thanks john
• Land Surveyor

  Scott D. Warner, PLS March 20, 2013 at 7:22pm

  Can anyone help Jazu?
• 

  john March 20, 2013 at 7:02am

  its very easy. first set the total station, that is, you put on tripod and level the bubbles. the place you set it should not be very far from the buildings you are checking for verticality. switch on the total station. you need not to set anything. bisect the bottom of one corner of the building and clamp the alidade of the total station. turn the telescope upwards as you sight through it. if the cross hairs move along the edge of the wall all along to top, then the building is vertical. but there may be small variations which are neglegable e.g deviations to left and right as you go up. but if there is a constant deviation to one side, then there is a problem with verticality.
  • 

    jazu > john March 20, 2013 at 2:25pm

    thanks mr john.

    but i would like to know the rectongular structure is it in vertical or not vertical.

    if not vertical how much the error.

    thats why i can correct my rectongular structure.

    please tell me the correct solution.

    iam in big confusion

    how much error how i can say.. 
• Survey Legend

  ⚡Survenator⌁ March 19, 2013 at 6:42pm

  This helpful document may help you with this...i used to have a tutorial but i'll need to dig it up when I get home..

  

  Total Station Document