What is meant by closing error? Explain graphical method of adjustment of closing error.

What is meant by closing error? Explain graphical method of adjustment of closing error.
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2 Answers

Answer :

Closing error: The distance by which the traverse fails to close is called closing error 

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Procedure:

1. Plot the traverse e.g. A’BCDEA to suitable scale and obtain magnitude and direction of closing error.

2. Draw a straight line A’BCDEA to some suitable scale representing the total length of traverse lines.

3. Mark on this straight line, closing error AA’ as Aa’ but to scale of traverse.

4. Join A’ with a’ as shown in fig.

5. Draw lines parallel to Aa’ through points B,C,D and E giving points b’ c’ d’ and e’.

6. Bb’, Cc’, Dd’ and Ee’ directly gives correction at stations B,C,D and E respectively.

Mark the corrections in same direction of AA’ at plotted points and locate new position of station points to give correct traverse A’B’C’D’E’A’. 

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Answer :

Closing error: The distance by which the traverse fails to close is called closing error.

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Step 1 ) Draw a horizontal line AA1 Equal to the length of perimeter of the traverse to a suitable scale

1) Mark the distances AB,BC,CD,…Etc on the line as per their lengths

2) Draw a perpendicular or (parallel to the direction of closing errors) to the line  AA1 Equal to the closing errors.

3) Join ‘Aa’ as shown in figure.

4) Draw perpendiculars B, C, D, E,To join the line ‘Aa’ at b,c,d,e

5) Transfer the ordinates to the respective stations on the traverse parallel to the  closing errors

6) Join the the new points which gives the closed traversed. A, B, C,D and A.


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