Define bench mark and enlist the types of bench mark.

Define bench mark and enlist the types of bench mark.
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1 Answer

Answer :

It is fixed reference point of known or assumed elevation. It is used either as a starting point for levelling or as a check while closing.

 There are four kinds of bench marks.

i. Great Trigonometrically Survey (G.T.S) bench mark.

ii. Permanent bench mark.

iii. Arbitrary bench mark.

iv. Temporary bench mark.
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