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Obstacle to chaining and ranging - Obstacle to both chaining and ranging
Chain surveying
Obstacle to chaining and ranging
Obstacle to both chaining and ranging
Obstacle to chaining and ranging
Obstacle to both chaining and ranging
I Method
Building is the typical example for this type of obstacle.
Select two points A and B on one side of the obstacle. Erect perpendiculars AC and BD of equal length. Join CD and prolong it past the obstacle. Choose two points E and F on the line CD and erect perpendiculars EG and FH equal to that of AC or BD. Join GH and prolong it. Measure DE. BG = DE.
II Method
Select a point A and erect a perpendicular AC of any convenient length(Fig(b)). Select another point B on the chain line such that AB=AC. Join B and C and prolong it to any convenient point D. At D, set a right angle DE such that DE=DB. Choose another point F on DE such that DE=DC. With F as centre and AB as radius, draw an arc. With E as centre, draw another arc of the same radius to cut the previous are in G. Join GE which will be in range with the chain line. Measure CF. Then AG=CF.
Building is the typical example for this type of obstacle.
II Method
Last modified: Friday, 29 April 2011, 8:50 AM